What Size Magnet Can ERASE a Credit Card?

[@humanoidmodel4217]

What size is needed to erase a credit card's debt?

[@svnerd947]

I guess it depends on how big the debt is and also how much said magnet can be sold for :)

[@sammyfromsydney]

You need an MRI machine. The method is simple. You sell the MRI machine and pay off the debt with the proceeds.

[@Slugsie1]

I reckon if you brought a magnetic field the size of the Suns into close proximity to the data centre where the account is held, that'd probably work. ;)

[@humanoidmodel4217]

@Slugsie, That's a bold strategy....but it might just be crazy enough to work...I'll start planning it...will contact you soon, wish me luck.

[@amidhmi5243]

You go Breaking Bad on the bank's Headquarters.

[@RichardBronosky]

Being able to see the magnetic data as a bar code is pure insanity. I can't believe I'm just now learning about this!

[@czdaniel1]

IKR -- This seems like something we would have seen already in Tech Media #GreatVideo

[@justAguyDs]

Mythbusters were filming an episode about it a long time ago and card companies caught wind of it and made discovery stop Adam Savage and crew.

[@czdaniel1]

+justAguyDs-- Yep. Who needs innovation when you can just bury your head in the sand *#Official** VISA Ltd. _Accounts Transaction-Protection Strategy*

[@czdaniel1]

Official Motto: *What you don't know, Can't Hurt You* _as long as you keep your head in the sand with Visa_ #InspiresConfidence!!*

[@theolodger]

ikr

[@TierZoo]

confession time: this one time in middle school I brought a hard drive magnet to Dave and Busters and repeatedly erased my game card and complained to the staff to get them to give me a new fully loaded card.

[@greenpogo]

brilliant! :P

[@Pandorana67]

Eyyyy its TierZoo! Fantastic channel btw

[@vect0rwolf]

Devs, nerf plz.

[@Reniconix]

Which perk do i have to spend points in to get this ability? On my human main it's built into the class, but i need to know for my alt.

[@TheReal_ist]

If only my local arcades had mag strip token cards. Then I probably would have done the same thing. Also how much was it for 30? and more and they would likely look into it more busting your operation.

[@Dr_OdayAdi]

My now-former physics professor would always tell us stories about how vital it was for them to carry cash if they wanted to go out after work because their credit cards were constantly being wiped since they worked around 1 Tesla magnets. 😂

[@NicholasA231]

Physics professor = probably pretty smart. Repeatedly bringing your wallet into 1T+ magnetic field *after* you've confirmed it can wipe your cards?... Well, at least it makes a nice anecdote for your students.

[@Dr_OdayAdi]

Nicholas Alt He always said, in his defense, it was a time they didn’t know much about the effects of magnets on credit cards. They learned the hard way when wanting to go out for drinks later and the cards always being declined.

[@fss1704]

+Oday Adi i'm pretty sure they knew but they probably forgot it sometimes... let's remember that cards at that time were a lot more susceptible to rewritings because of low magnet permanence.

[@axisdroid1211]

N

[@anthonynorman7545]

@@NicholasA231 what does understanding high level physics have to do with remembering to remove a wallet or credit cards?

[@erictaylor5462]

Just be careful in Hawaii. *THE FLOOR IS LAVA*

[@czdaniel1]

On a Spanish island, they *Lava their hands* EditorNote: That is _they_ singular. *WHICH DOES EXIST IN ENGLISH* despite Miss-Wilson-My-7th-Grade-English-Teacher's lies!!!

[@erictaylor5462]

I would not recommend lava for your hands. It is very bad for the skin. Actually singular they is a rather recent replacement as the pronoun to replace him or her when the gender of the subject is indeterminate. I'm not sure when it came into popular use, but most likely Miss Wilson may not have lied, it's just that information is out dated. It reminds me of Abraham Lincoln's computer. Before the invention of the electronic computer, the term was used as a job title for people. That job was eliminated by the machine, so you'd be right to say that computers were the first job replaced by electronic computers. I like to say Lincoln had a computer that understood and responded to to voice commands. "Larry, add up these figures will ya?" Sure thing, boss"

[@RomanoPRODUCTION]

@@erictaylor5462 hmmm you mean that Larry was modern day Alexa (like in "this is so sad Alexa play Despacito") so Alexa is a fluid transgender "they" ?????

[@StopChangingUsernamesYouTube]

That's nothing. Just hop around while grasping seat cushions with your feet. Not touching the floor? No problem.

[@cavemann_]

technically all of Earth's floor is lava :thinking:

[@DaHaiZhu]

The other reason you cards don't get erased in your wallet/phone case is because you're generally not rubbing them against the magnets in there. Mythbusters found that just placing a magnet against a mag-stripe wouldn't erase it, its the motion that mucks it up.

[@grahvis]

Da Hai Zhu Indeed, you can magnetise a piece of iron by stroking it with a magnet.

[@christianbarnay2499]

Agreed static magnetic field is inactive. Otherwise the earth's natural magnetic field would wipe any magnetic tape over time.

[@davefoc]

@@christianbarnay2499 Hysteresis is a thing. If the magnetic field is below the strength required to magnetize something the magnetic field just springs back to what it was before it was exposed to the magnetic field. When the magnetic field is above the level required to magnetize the stripe the strip is magnetized in a way that it doesn't spring back to what it was. Hence no matter how you move your card in the Earth's magnetic field you won't affect the magnetic pattern on your card. The Earth's magnetic field is too weak to modify the magnetic pattern on the card.

[@carlovincetti1352]

Maybe people in the entertainment business and speakers would be the only people to worry about it in their pockets.

[@NormReitzel]

I worked with multi-tesla NMR spectrometers and have had experience with erased credit cards. You should know that mag-stripes come in two flavors, low coercivity (natively brown) and high coercivity (natively black). The Hi-Co cards are a lot more resistant to large fields. Very small fields (like your first magnet) have high dB/dt and are really good at erasing mag stripes. Loved the video!

[@KJMagnetics]

Great video!! Thanks for using our magnetic field calculator :)

[@hola_chelo]

It's a great tool, but why don't you use Tesla instead of Gauss? is there an advantage?

[@hola_chelo]

Not really, It's like inches and meters, the SI (International System of Units) unit for magnetic field is Tesla which is equivalent to 10^4 Gauss.

[@stan_dinghere]

lmao

[@anshitkumar6347]

@@hola_chelo I'd have used Tesla but they don't deliver on time

[@KJMagnetics]

No advantage. We just like working with whole numbers. It's the equivalent to paying someone with coins instead of bills. In the end, its the same, but it's much easier to just pay with bills!

[@thesfslade]

Since you edit video and like to see magnetic tracks, you might be interested to know that from the invention of video recording in the mid '50s until the early '70's, 2 inch video recordings were physically cut in order to edit. The location for the cut was found using magnetic developer (fine iron oxide particles suspended in a liquid that would evaporate. The exact location was found with a microscope to see the frame start on the control track. Once cut, it was taped together in a way similar to audio tape. It was hard to do well and most shows tried to avoid the need. The most notable exception was "Laugh In" which used extensive physical cutting along with off-line film editing and film style audio post production to create a unique production style.

[@jc.1191]

I'm an audio guy. We had to rock the reels back n forth to scrub it. You had to learn by ear to identify transients. Not fun.

[@PowahSlapEntertainmint]

Now do "What Size Credit Card Can Erase a Magnet?"

[@clayberri]

I swear every video k click on u hAve commented on 😱

[@Blox117]

your moms credit card

[@vari1535]

W-wait what video did I see you on?

[@vari1535]

Oh I know... you only need a kazoo for music production.

[@adminmine7066]

What video do you not have a comment on at this point... lol

[@XSpImmaLion]

Magstrip is already a relic... at least outside the US. In Brazil, they've been replaced like... around 10+ yrs ago now. Because of course, cloning already had become rampant here all these years ago. Weird thing is, nowadays most credit and debit cards still have both (magstrip and chip). So the information is still there. But banks automatically flag purchases done with magstrip save very specific recurring cases. Like people who live somewhere in Brazil where there still are magstrip only readers... in theory, I don't even know if such a place exists. Personally though, I haven't seen magstrips being used for at least half a decade now, even though PoS machines still have the slot there. In fact, the last time I saw an ancient method being used wasn't even magstrip... it was in my mom's 5000 people hometown where the bus station still had one of those credit card guillotines. Remember those? Highly insecure, takes a full carbon copy of your card for transactions. Now, THAT was a bad idea. But they updated the system 5+ years ago. My current bank has biometric vein scanners on ATMs. For basic transactions, you don't even need a card anymore.

[@adamb89]

Visualizing the magnetic stripes was my mind blow of the evening. It's ranking up there on par with the time I discovered cell phone cameras can pick up infrared light. Remote controls blink brightly! Black sensor panels become transparent when viewed only in infrared! Awesome stuff.

[@0MoTheG]

Black nylon looks white in NIR

[@reddragon3132]

I love that in America, the concept of the mag strip going away is still a thing. I literally haven't seen one used this decade in the UK. Chip usage is now decreasing due to contactless

[@DampeS8N]

yeah yeah, but if we get fraudulent charges on our cards we just tell the CC company and they go away - no questions asked.

[@reddragon3132]

Pretty much what happens here

[@lmaoroflcopter]

@John Doe aside from ease of use, convenience and speed... Ya know. The obvious stuff. Oh the higher level of security helps too, you know given the chip protections in combination with an actual pin Vs a scrawl on a bit of paper verified by a bored and inattentive cashier.

[@KaliTakumi]

@@DampeS8N Why did you say this as if you knew this wasn't the case in the UK? 🤔 You were clearly wrong

[@jonathandpg6115]

M3ta7h3ad not just that but the cashier has no REAL way of verifying the signature either. It's basically useless.

[@alexstremme6839]

Thanks a bundle for all the good you do to make the world a more rational (thus better) place. More of this is needed.

[@georgetrapp6666]

I had a habit of carrying singing magnets in my pocket. Or Sizzlers, as they're sometimes called. The two elliptical magnets, that if you toss them, they bounce together and make that 'sound'. I stayed at a hotel, and my keycard kept refusing to work, and I needed a new one at the desk. I hadn't drawn the correlation at the time. I didn't have any credit cards at the time, either.

[@vasilikiv]

Congratulations for hitting 1 million subscribers!!Well deserved!I loved "Physics girl" since the beginning!Many kisses from Greece!

[@SuperDerfmaster]

Interesting info, that I would never have thought to look for. Thank you for another fun video.

[@mirijason]

Great video! Just one more experiment I would like to have seen you do : Use the iron particles to see how readable the credit card was at 8 sheets and 6 sheets. Like was it all or nothing, or rather a more progressive erasement in which case it would have provided a measure of how resilient the magnetic reader is to corrupted data.

[@nesnioreh]

Swede here. I haven't swiped a card in maybe a decade. Chips took over many years ago. And now we're going touchless.

[@reddragon3132]

Same in the UK. It's odd how far behind the US is

[@rednafi]

I'm not an American but in the case of tech industry....Error 404: Europe not found

[@911Vivo]

As a german guy, what is even a credit card?

[@reddragon3132]

Arguably that's what makes it so odd. You're correct that Europe doesn't have much of tech industry so it's weird that we seem to be so much more technologically advanced when it comes to credit cards.

[@uninterruptedrhythm4104]

RedDragon did you even watch the video? She literally said its mainly on Hawaii, the rest of the US mainly has chip and its going contactless too. Lol at Europeans acting like they've advanced 100 years because credit cards.

[@homerotl]

Great video! You mentioned hotel key cards for being weaker. What about car parking lot tickets? those paper ones with a small mag stripe on it. In my experience, those get erased way easier. Even happened with my phone case a couple of times.

[@potteryjoe]

I was expecting a much greater resilience of the information on the card strip. It's a miracle I haven't already erased mine

[@tomewyrmdraconus837]

Magnetic fields follow the inverse cube law (double the distance, cut the power by 8-fold), and the actual forces are pretty weak. So you get very far away and the force becomes positively tiny. It's not until you get really close that the near pole starts to be able to overpower the effect of the far pole in a thin magnet.

[@fss1704]

take a look at magstripe kinds, they have different strenght levels for different applications.

[@gregiep]

This was excellent!I loved the visual of dipping a credit card into the iron powder, very cool!

[@CHALKND]

As a math person, when I saw the iron oxide on the card my brain just jumped straight to applications of symbolic dynamics.

[@EweChewBrrr01]

Thanks Dianna. This has helped me since I have 10 neodymium button magnets sitting on my bench and, funny enough, just today I wondered if they were doing nay damage to my cards or computer components as I walked passed it. Seeing how I'm over 30 cm away from it I now know, thanks to you, that I'm safe.

[@A_Man_In_His_Van]

"why do you have all these credit card manufacturing machines?" "Research" lol

[@subbss]

That's normal if you are a professional security researcher.

[@arisuki]

I’m from Chile and we made the move to chips and contactless tech few years ago, and our bus/metro pass has always been contactless. However, watching this video I’ve remembered the time I “deleted” the info on my pass by keeping both my phone and pass in the same tight pocket. Also last year there was a huge issue with contactless tech here bc the range in which the card could be read (by different devices) was wider than expected (card-kept-in-a-wallet-inside-a-bag wide). So it might be fun to find other culprits on our damaged cards!

[@RoguishlyHandsome]

I want to hear the story about when he ate iron oxyde.

[@Sembazuru]

I remember when I was in early elementary school (so, early '80s) my father borrowed a programmable calculator (Texas Instruments, I think) from his work. This calculator had an integrated mag-stripe reader that took specialized strips (going by memory, roughly 3" x 1/4"). One was able to use these magnetic strips to write and read simple little programs. I was too young to really understand how (or even why) to program the calculator, but my older brother and father got a lot of enjoyment of the calculator.

[@johnlong2k9]

Any day with a new Physics Girl video is a good day!

[@czdaniel1]

What's Qesu?? I presume from your _Ankh_ foto that Set is referring to the Egyptian god, _Set._ But what's Qesu?

[@stevetakacs654]

Get well Diana. I've been following you and I really enjoy your videos. Keeping you in my thoughts

[@polinanikulina]

i went here to see if anyone had aknowledged how cool that farmers market dude looks

[@pauljoyko5320]

Polina Nikulina He looks like he is a friend of Vlogcreations/Rosscreations

[@williamkrueger268]

Once upon a time I was computer repair tech. There was a product named Magna-See that we'd use to inspect track alignment/signal-quality on the read/write heads in magnetic tape units. One would dip a piece of recorded mag tape in the fluid, remove it, and let the solvent evaporate. You could see the Flux changes on the tape thanks to the incredibly small magnetic particles suspended in the fluid & that adhered to the mag tape. I don't think that product is around any more but there is one named Kyread SDF-130A that looks like an equivalent. That might be a handy resource for any future experiment where you need to visualize magnetically recorded signals.

[@Jacob_AL_Moore]

Woah! You're friends with sammy!? I've watched so many of his Defcon talks; he seems like a really cool guy! Loved the video too!!

[@Prism988]

I've always wondered (well not always, just recently) if chips and paywave transmit fixed info every time. Now I'm wondering how the info is changed. Great video as always!

[@eugyy_]

"The reason I was so *_shooketh_* "

[@greenwave819]

She said, "Are you trying to erase my credit card, or is that just a large magnet in your pocket?"

[@bendingsands87]

I've read that two cards placed stripe to stripe can destroy one another. Also, chip cards may be secure, but they are just as easily stolen. Try the chip 3 times at almost any pin pad and you can slide the card, then you can just press enter when asked for a pin to run a debit card as credit. From working in a grocery store I see this all the time and at the cost of angering a potentially legit customer, we let it go. You can thank good customer service for most retail cc fraud.

[@jonathandpg6115]

That's where credit card companies come in and their fraud detection. The idea is to be safer and obviously the goal is to remove the old tech once this one is stable.It just takes a while.

[@VictorRivarola007]

I have personally erased both 3.5" and 5.25" floppy disks with refrigerator magnets! Both types of disks where low level unformatted, but after a simple call to the FORMAT DOS utility, they where perfectly usable again. Any data previously stored in the disk was gone forever, however.

[@radix4801]

IIRC, his "magspoof" device is exactly how Samsung Pay works. Samsung phones are able to send the magnetic data without a card present.

[@radix4801]

Yes, I should have said this is a feature that Samsung has that makes it different than the others. It also does NFC.

[@user-os8sq3uh4n]

Radix it was NFC and MST developed by LoopPay that Samsung bought. MST is not in the other NFC systems.

[@IceMetalPunk]

Yep, it is! I used to work in a popular supermarket here in the States, and for whatever reason we were very slow when it came to upgrading our hardware. We were one of the last stores to get the chip readers, and when I left that job just a few months ago, they still hadn't gotten NFC payment hardware. Which meant whenever someone would ask, "Can I use Apple Pay?", I'd have to be like, "No, but you can use Samsung Pay!"

[@R4T1N4]

Both are using same technology to emulate magstrip but Samsung pay is way more secure. Samsung pay generates different information everytime using its network. Just FYI :)

[@seraphina985]

+Sungho Lee Another great thing about using apps like that is unlike the card itself that can be tricked by any fake reader at any time you can turn the NFC feature off on a phone when you don't intend to use it. While off you could wave a reader at it all day even a legit one modified to just save the card numbers and it would be like there was nothing there.

[@thebruce0]

The only thing with chips is the one-read payment. Demonstrated recently by a test with someone's card in their pocket, and another with payment terminal set to 'tap' - without touching the pocket the payment was able to go through with him noticing. A chip with a secondary verification (like the pin) would be better than a one-tap payment.

[@mosheackman6095]

Diana: I need to know how to replicate credit card information...for, uh... science

[@TheReal_ist]

Theres lot of articles in the more hidden web. Search away young one.

[@loicbenadiba9476]

@@TheReal_ist yes its pretty easy but it's bad you see

[@fss1704]

laserspoof's what there is.

[@Cams250]

Yeh five years minimum isn't worth the little amount you'll be spending.

[@LikeOnATree]

Awesome video! I could sit and watch Samy in his lab for hours, so cool!! Thanks for the video!

[@kevincrawford2372]

I moved to Washington DC from the UK last year. Amazes me how many places here swipe my card and ask for my signature. Been many years since I did that in the UK.

[@uninterruptedrhythm4104]

Kevin Crawford Its because many stores still havent changed to chip

[@EdSmiley]

Hey @PhysicsGirl Using paper as a magnet spacer bings back an old memory. Back in the day I used to hack single reel to reel tapes by placing a couple of layers of paper over the writing head. The result is that I could double track by recording over one sound by not fully erasing the previous. I could use one tape recorder playing as input, and record it twice and get an echo.

[@TheAdventureAuto]

We've gotta keep an eye on that friend of yours.

[@charlierw123]

He's already been arrested for hacking once. Lol

[@TheOzumat]

Fake news.

[@IceMetalPunk]

The weirdest part is that the thing he was arrested and charged for was mostly harmless. It just added him to everyone's MySpace friends list and added "Samy is my hero" to their profile. But for that, he was fined $20,000 and 3 years without internet. Kind of an overreaction, if you ask me; a slap on the wrist would have been enough for such a harmless prank.

[@dsp4392]

@@IceMetalPunk 3 years without internet is how you get a geek to build those pipes. No prison needed.

[@actsrv9]

@@IceMetalPunk God damn, that's a terribly harsh punishment. 3 years without internet would lobotomize me permanently.

[@Texicles]

In high school, I saved a paper on a 3.5" floppy on my home computer to print out on the school computer. I checked to make sure the save was good before I took it out of the computer at home. In order to make sure I didn't forget the disk, I tucked it into the flap of my wallet that night. I put the disk in my pocket when I was getting dressed the next day, and when I got to school the disk was blank. I've been operating under the theory that the mag stripes in my wallet erased the disk, but now I'm not so sure. Would be cool to see some testing on what magnets do to disks, since you're tossing magnets on old technology.

[@SpriceMachines]

Hillcrest market 🤟

[@dear_imran]

No likes in tick mark Hmm strange

[@bidaubadeadieu]

Excellent video on a topic I knew nothing about beforehand! Thanks for working hard for us!

[@kevinbs05]

And this is how you get a call from your credit card fraud department.

[@LaercioCruvinel]

Please make a video explaining why light slows down in dense materials. I find it difficult to accept theories that imply photon interaction with the material's atoms (for example, a photon being absorbed and then re-emitted by an atom) because if that was true, light speed would diminish progressively, more and more, with the length of the denser mean. Thanks!

[@tripletoruses]

*buys multiple magnets* *cannot read card*

[@theradlanders]

I have been trying to find this answer for days - thank you for sharing this experiment and knowledge! Now I finally know why my cards keep getting erased and what to change to make it stop. (My current phone case is configured where the card slides RIGHT over the wallet's magnetic closure.)

[@999sian]

So i am from the UK we complety stoped useing mag strpes years ago but our debt cards with cip and pin and contactless still have the magstip for backward complaibilty reasons

[@BlackJar72]

That how credit and debit cards are in the U.S. About 90% of businesses use the chip, though there are a few hold out. OTOH, government issued cards used with some of welfare programs (e.g., "food stamps") are still mag-strip only.

[@jonathandpg6115]

It's like that in most places. The U.S. is the furthest behind but they are almost caught up behind.

[@K8andNat]

Which is exactly how it is in the US.

[@999sian]

I mean we never use mag strip like the whole county has moved on to contactless within the last few years which is less secure than chip and pin

[@Nemoticon]

This video was WAY more interesting than the title suggested... the mag-strips being shown after the card was covered in that powdered carbon was fun to see and explained a lot.

[@thebruce0]

"Why do you have these things!?" "Research!" hah For science!

[@aianyoung]

That was a great video. Once again, thanks for making cool, educational stuff and putting it on the internet!

[@onelungg]

mag stripes, wow, laughs in European

[@Old_Ladies]

Also laughs in Canadian. I don't remember the first time I got chip cards cause it was so long ago. I am frustrated that some stores don't have tap to pay like Walmart in Canada.

[@RomanoPRODUCTION]

@@belligerentcabbage4438 right European soy boys

[@TDrudley]

People use chips still? I just use the wireless part of the card.

[@Gribbo9999]

@@TDrudley You still use a card? I just tap my phone which acts as a card clone.

[@dsp4392]

I've heard some of them still use cash like cavepeople.

[@ianmckenzie8685]

Some years ago I was staying at a hotel (in Singapore) with a mag-stripe door "key" to my room. It kept failing & the front desk kept having to re-program it. I used to keep the card in my cell-phone holster. After day 6 I realised that it was the magnetic clasp on the holster that was corrupting it.

[@lvkasmusic]

Wait, you don't have chips fully implemented?!

[@CaseyJMoore]

Love that you are repping a Starset T!!!

[@jmack4275]

Let's learn how to hack anybody's credit card yay!

[@tondriasanders6306]

Once again, you have blown my mind, Diana! It is insane to me that when I was born computers took up massive rooms and now I’m carrying around at least four microprocessors in my wallet EVERY DAY! Oh my gosh! I just realized what it must feel like for my distinguished elders. The things my grandparents have witnessed in their lives. The awesomeness... 🤯 I think my brain might be broken now.

[@proffmongo]

the man selling the chips doesn't have a chip reader. hmmm.... a thought to ponder on how the universe works.

[@trod146]

If you need to buy a chip why would you already have one? Hmm.. A thought to ponder on your common sense.

[@robertt9342]

Nice to see the US has caught up. The mag stripe was in common use just a few years ago in the US. Where I live, the chip was in common use for about 20 years where they wouldn't even let us use the mag stripe.

[@zachheilman784]

AHHH don't post pictures of your credit/debit cards! That's just asking for them to be stolen! (see the user "needadebitcard" on twitter).

[@AnEvolvingApe]

The card is expired in 2017 so I don't think Samy is worried.

[@jonathandpg6115]

They're prepaid cards they mess with. They aren't worried.

[@katherineg9396]

Very helpful. I always rub the magnetic stripe on old credit cards with one of my ever-increasing collection of National Park Magnets. It's good to know they're so useful! (Just got a new Death Valley magnet a week ago!)

[@aspiringcloudexpert5127]

That hat is just marvelous.

[@TheHayes32]

Thanks again Sammy for helping me find the combo my Master Lock.

[@Frosty-oj6hw]

Samy is my hero.

[@jorgejedieduardo]

AWESOME as always!!!!!! Never stop teaching us Dianna! Thanks

[@RakshithPrakash]

Yup, Samsung pay does the same thing I use it all the time everywhere

[@DerrickBraga]

Except that Samsung pay uses a token instead of your credit card number and also sends one time use data.

[@RakshithPrakash]

@@DerrickBraga yeah , also gives a virtual card with different last four digits

[@TheAsianMelon]

I just had to explain this to the store lady... Very interesting

[@john1937]

Something I would like to point out about the Square stripe readers is that Square's instructions tell the merchant to make sure that the phone or tablet's volume is turned all the way up so that the device has the greatest sensitivity for capturing the signal through the headphones port. It also states that one should swipe the card SLOWLY. Running the card through the reader as quickly as the guy at the Farmer's Market did would cause the card not to read even when in pristine condition. When one swipes a card, it should take most, if not all, of a second to make just a single pass. Any faster than that and the reader will report a bad read more often than not, especially when swiping back and forth five or six times in a single second as seen in this video. Both of these issues could have affected the results of this experiment, so I would like to suggest that if Dianna et al. would like to test for more accurate results, take both of these factors into account when repeating the experiment. If the only desire for this experiment was to test whether magnets could affect magnetic stripes on cards, then no need to re-run this experiment since it already proved that point despite the procedural errors.

[@BOBimusRex]

Every Samsung owner with an S7 or newer phone has a "mag spoof" built into their phone. That's how Samsung Pay works, using nfc to send the same code that the strip of your credit or debit card uses.

[@PeteOhki]

With one added difference, Samsung Pay uses the same security measure that chips use: the random card number. Also I think it was first implemented with either the S5 or S6 models mere days before NFC (what Apple Pay uses) became a thing.

[@BOBimusRex]

It would be interesting to try this iron oxide experiment with Samsung pay. Maybe set a price of paper on the back of the phone and sprinkle the iron oxide on the paper, and then use your finger print to initiate payment and see what happens.

[@PeteOhki]

@BOBimus Rex: I like that iron oxide idea. To further @Chris urquhart's comment, MST and NFC are two different technology & hardware. MST uses magnetic field pulses (probably utilizing a coil of wire), while NFC uses short range radio signals. These days, Samsung Pay can now use both MST and NFC.

[@TheOtherBill]

Dianna must one of those old fashioned iPhone people if she wasn't aware of this years ago. SamsungPay with MST was available on the Galaxy S6 in 2015. I chose Samsung Pay over both ApplePay and GooglePay for just this very reason 2 years ago. Never regretted it for even a second.

[@PeteOhki]

@Chris urquhart: The experiment would still be interesting to see just what would show up. May or may not see anything considering the strength of the generated magnetic field, and the speed of change to simulate the 1s and 0s.

[@frzstat]

Great episode Dianna - thanks!

[@Quetzalcoatl0]

Contactless cards being safe ? XD yea right.

[@reddragon3132]

They are in that if someone intercepts the information it is of no use whereas mag strip works forever once you have the data. I will give you however that they're not safe if you go out and lose it but then so is any card as you can just buy stuff online

[@lmaoroflcopter]

@@reddragon3132 1. They are limited in maximum transaction size. 2. Anti-fraud will pick up abuse pretty rapid these days, they've a large data set to tune on. 3. Any contactless payment is treated as "cardholder not present" meaning contesting is a non-issue. It's down to the retailer to prove you were the authorised individual to be using the card.

[@fredflintstone9657]

Face it....pretty much nuthin'is safe. Bad guys are smart.

[@deathwatch27]

Cool vid but would of loved to hear about how the contactless system works and 'if' it's more secure

[@gulktroktet]

The "magspoof" technology where you use a device to emulate swiping a real card on a traditional card reader exists in some phones already.

[@czdaniel1]

Somebody here said Samsung phones do it

[@jonathandpg6115]

samsung pay not the phones but the app yes.

[@gulktroktet]

It's something that requires a physical piece of hardware, so it absolutely has to do with the phone itself.

[@fss1704]

+K. you can record a magstripe using a tape player and make a micro magspoofer using a 3v battery and an lm393 and some wires to a headphone jack.... just like mine

[@Kilt_Bilt]

I Love your videos Dianna, they are just the right balance of super smart and super silly.

[@HungryGuyStories]

I'm disappointed you didn't explain the inverse square law when you said "the strength goes down the farther you are from the magnet."

[@KaliTakumi]

Same, I thought she would mention it

[@davburns]

Magnets don't follow the inverse square law. There's an inverse cube law for perfect permanent magnets (ie, magnetic dipoles), but changing magnetic flux (like when she moved the magnet across her card), or a magnet that's a real-world object requires more math than I'd want to sit through in a youtube video. I suspect that's why she used the magnet supplier's calculator.

[@KaliTakumi]

@@davburns Interesting

[@peppers1587]

Same as gravity

[@HungryGuyStories]

@David, that just goes to show that she should have explained it :-)

[@SquidgyBidgey]

Cool. I nice follow up vid would be to look at security of chips vs contactless.

[@morbid1.]

I love payment via chip card... srsly less interaction with people - better.

[@lol-cq2iu]

Neurotyczny Kot use nfc duh

[@tomewyrmdraconus837]

chips so dang slow. Contactless (NFC) is leagues better

[@jonathandpg6115]

Chips are NFC...........

[@fredflintstone9657]

You must be a hoot at parties....

[@foxtrot2320]

I.. have never used a card swipe that worked, tho as a kid, I have always loved the concept of swiping it

[@nabila2180]

NOTIFICATION SQUAD!!!where you at??

[@ackurus3222]

Given this information for maximum security: cover the CC number, expiration, CCV, then erase the magstripe, and then the only way to exploit the card would be to physically posses it.

[@kevinm3751]

What sort of dude has not one but two man buns? That is just wrong no matter how you shake it!

[@AnEvolvingApe]

The sort of dude that lives his life the way he wants. One of the best things about living in a modern society.

[@kevinm3751]

To each their own!

[@AnEvolvingApe]

We're all humans with nothing separating us except ideology.

[@sophiejones7727]

Better question: is there such a thing as too many buns? we have already established that the subject of this sentence is masculine calling his hairstyle "man buns" is unnecessary.

[@ianmacfarlane1241]

@@sophiejones7727 They are called man buns whether you deem that unnecessary or not.

[@drysori]

2:55 Black iron oxide is not toxic and iron is an essential nutrient, so yes you can eat it in small amounts. Just don't breathe the dust.

[@AlwinMao]

Before watching the video I guessed the small magnet and large magnet would have about an equal ability to erase the credit card (the small magnet erased when it was touching, and hence the large magnet also has to be almost touching). Here's the reason why: simple electric fields from point charges are monopoles that decay as 1/r^2 (inverse square), which many people are familiar of. But there are no magnetic "charges" and the familiar magnetic fields are dipoles: an extra order of "pole," which means they decay as 1/r^3. The surface of a spherical magnet is distance r from the center, and the volume of a magnet scales as r^3. The total field strength of the magnet also scales as the volume (more aligned spins), so the strength at the surface is surprisingly constant: a larger magnet is r^3 stronger but the surface is further from the center and the field at the surface 1/r^3 weaker. All magnets of the same material and similar shape basically have the same surface field (to within order of magnetude) and will be equally bad for your credit card.

[@chiefbosnmate]

Another great and useful episode! Thank You

[@drflash36]

Some years ago, I worked in a research facility that had large, (shielded?) superconducting NMRs there. We employees were required to wear IDs w. mag ID strips in them. After several people had their IDs erased by that SC magnet, they measured the magnetic field & put red tape around it, with signs warning you to not step beyond the tape w/o first removing our IDs!

[@luismijangos7844]

Amazing video, Dianna. I love your channel.

[@JJJthebest]

This was actually completely cool! Great video, and shoutout to Jabrilsssss

[@XavierXonora]

In Australia pretty much everything is contactless now. Nobody uses chip and pin unless it's for large purchases (over $100 AUD). I process payments a lot and it's about 25% cash, 10% chip and pin and the rest is contactless. Most transactions are $5-50 though so that makes sense.

[@CrankyPantss]

That was all very interesting. Thanks, Dianna.

[@kinouillek]

That was very cool. I love how we could see the mag stripes.

[@Seegalgalguntijak]

I think that any Neodymium magnet is strong enough to erase magnetic memory like on a magstripe, even the weakest N35. If you touch it directly, that is. A really strong N52 magnet would probably even still be able to erase it from an inch away or so.

[@christianbarnay2499]

The only places in France that only use magstripe are highway tolls (and they don't require signature). It's a trade off to ensure fast flow. Everywhere else magstripe readers are only used with foreign cards that don't have a chip. if your card has a chip they will refuse magstripe payment on the suspicion of fraud.

[@DingXiaoke]

It really fulfilled my curiosity when he pull the card out of the iron powder bag. Ah huh~~I can see those magnetic binary numbers

[@marcosbeni5875]

That guy's device that mimics credit cards comes built into most Samsung Android Smartphones. It's called Magnetic Secure Transmission (MST). It allows you to use your phone to pay using Samsung Pay, even if the terminal does not support contactless payments (NFC).

[@elmikeomysterio5496]

Dunno if this has been mentioned yet because I didnt bother checking comments but... That first magnet is popular with "biohackers" as a subdermal implant. It lets you feel electromagnetic fields and test metals. I have one in my right ring finger because I bet someone it wouldnt work. 3 years later, it's still there and definitely works.

[@jamesfunk7614]

I heard about something that happened years ago, before access badges went RFID. The magnetic strip on a batch of access badges was too strong.Employees who placed the badges in their wallets found it was damaging the data on some of the stripes on credit cards.