Metric vs Standard, Imperial or SAE - Wrenches, Sockets, Bolt Size Chart + Mechanic Math

[@f-puppet]

I like how you spaced the SAE measurements in relation to the metric measurements, so that we can have an idea of just how much difference there is to them. Thank you very much. Just what I needed in my toolbox. I've printed and laminated a few of these cards thanks to you!

[@HartzHomestead]

Glad it's useful to you. I kept running into this situation, so I designed the chart to be as practical as possible.

[@maverickp-5138]

😮😮😮😮😮😮😮😮😮😮😮😮 1:07 😮😮 1:14 😮😮😮😮😮😮😮😮😮😮😮😮😮😮 1:35 😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮😮

[@Prolific_Knives]

This is likely the best conversion chart that I have seen out there describing the similarities and differences between mm and sae sizes. Thank you sir.

[@tinamarie4875]

Thank you for the valuable information, plus I also appreciate that you go right to the point and not try to humor us withlame jokes or unnecessary silliness or annoying background music and etc. Keep up the good work!

[@HartzHomestead]

You're welcome! Well said. I've seen so many videos that waste a lot of time. I know how frustrating that can be, like, get to the point, people! Tell us what we need to know.

[@evarage57]

Thank you for making this video. I am a scottish mechanic and ive only ever worked with metric bolts and nuts. i am about to travel to germany to start a new job as a heavy equipment mechanicfor the US Army. This has helped alot!

[@HartzHomestead]

You're welcome! I've had a couple vehicles that have a mix of both metric and standard, so having that chart saves me a lot of time.

[@brandonr.5625]

Awesome working on that currently too :)

[@shtika]

Excellent chart. Downloaded , thank you. I do have 17/32 , 19/32, 21/32 and 25/32 sockets however never used them except for show and tell and bets with co-workers.

[@lastking2114]

This video should be showed in schools! Thanks for making the chart readily available to print!

[@Namastayawayy]

Totally agree. Beats some of the unnecessary crap that we are taught in school. This at least is useful.

[@JNC1973]

You my friend are a life saver. I've been trying to figure for days what kind of bolt I need to replace that held on my clutch pulley wheel on my mini bike and nobody could answer my question. Now after stumbling upon your video I need Metric cause it does say 8.8 on the bolt head. I learned something new today. :)

[@HartzHomestead]

I had to do some research myself in putting this video together and found it's very handy being able to read bolt heads. Glad it helped! I'm surprised actually at how many bolts in the US are now metric.

[@dandannoodle19]

never had to work with standard, this similar comparison of metric sizes to standard helped me place the sizes better in my head as I will begin working with SAE. TY so much for the video and the image for later jogging

[@growthmindset6549]

Thank you for such a comprehensive video! Just learned so much. Keep up the good quality videos!!

[@IDIturboDiesel]

There is a substitute for 15mm and that is 19/32 which some tool sets have.

[@adventurevin7600]

This us great! I downloaded and printed a few of the charts to give to friends. This helps a great deal when I need to hold an opposing nut attached to a bolt. You explain it so clear and in minimal time. Thanks for providing the chart!

[@HartzHomestead]

Glad I could help! I use this chart myself quite a bit. Very handy.

[@boshintang]

Most useful video I've seen in a very long time.

[@DennisRackers]

Thank you! Your table on interchangeability is the only such document I found in a quick search and it will save me from time and hassle of doing the math or trial-and-error with the wrenches. I found your table while looking for a way to reduce the number of wrenches I carry when I'm away from my garage tools.

[@mysticjedi6730]

Thank you for this video. I will print off a chart like this and tape on all my tool boxes. Great idea

[@maryhoffman2547]

Exactly what I was looking for. Thank you so much for sharing your knowledge with us! I am definitely printing the sheet out to put up in my toolbox.

[@anocri]

Fantastic informative video. Didn't know the differences all these years, and glad to know the differences. Was using the wrenches based on the fit. The chart is awesome so I can dance between SAE and mm in an attempt to find the correct size wrench for a bolt.

[@HartzHomestead]

Thanks! I love practical information like this that makes it easier to do things.

[@mewyattt]

Thanks for this video! After watching this, I'm buying metric and supplementing in SAE.

[@HartzHomestead]

Good plan! You could have full sets of both, but Metric are most common these days, filling in with SAE that have no metric equivalent.

[@TheRAMBO9191]

Old video, but ima guna try n print this chart and laminate it.! Thank you so much. I'm 32 never learned tools but starting to get interested. Had tons of family in construction but by time I hit 12 most past away including my dad at 9. Rough childhood but I know I had better still than most out there. I'm guna try to watch this video over n over to get an idea in my head.

[@HartzHomestead]

If you have a printer, you should be able to download the chart and print it.

[@wondersteven]

It's amazing how much info you packed into just 4.5 minutes or the metric equivalent of 4:26. Thanks.

[@HartzHomestead]

Thank you, actually closer to 4.433...minutes. At least Metric and Standard time is the same. Imagine if a metric day had 10 hours of 100 minutes, made of 100 seconds each. Why divide a day into 24 hours of 60 minutes each, except it's always been that way.

[@asdfnone1346]

I measured my lug nut at 17mm and bought 17mm metric socket, boom! it didn’t fit! I think 19mm might fit after this experienced. Thank you sir for this information!

[@norge696]

Go on tekton and pickup a master socket set. No skips at all!

[@TheSkylark16]

Great video! I finally use my 38mm sockets for 1 1/2" since SAE tools are way more expensive in my country! It's only 0.1mm diff

[@HartzHomestead]

Especially with the larger sizes, they are almost interchangeable. The bigger you get, the less relative difference. Sorry, my chart didn't even go to 38 mm, but since 3/4" is almost exactly 19mm, doubling it we can see that 1.5" = 38mm.

[@Ronnieyotob]

Thanks for this info, and chart! Found out the hard way these aren’t 1-1 interchangeable 😖 one stripped caliper bolt later I won’t make that mistake again!

[@sonicknives]

Thank you! Ive only used metric and soon will need to use standard tools for my new position. Many thanks!

[@kimifan06]

on race cars we use the 7/16 and 11mm interchangeably on the bleeders screws

[@sneakysnake109]

I downloaded it. Thank you for the chat and the video!

[@CristianHernandez-px9uz]

Very informative man… God bless you!!!💯

[@SherryAdcox]

Thank you. I have not used these ranches much in my life. Now I am on my own and having to do work around the house. I am very confused. This helps a lot.

[@toribenita_kyo]

It's possible to substitute a 13-mm wrench with a 1/2" one, but it's going to be roughly 0.3 mm oversize (1/2" is approximately 12.7 mm). Adjustable wrenches can be used with both metric and inch nuts and bolts, but you're going to be sacrificing strength (and durability) for adjustability.

[@HartzHomestead]

Good points. An adjustable wrench is more likely to slip a little if it takes a lot of torque and thus may damage the bolt head. Sometimes a 1/2" wrench will fit a 13 mm bolt very snugly, but a 13 mm wrench will be very loose on a 1/2" bolt.

[@michaelkulman7095]

Yes, people miss that some substitutions only work in one direction. When I was young few had metric sets and as foreign cars became more common we made these subsitutions and even picked up extra SAE wrenches in some sizes to file down the open end to fit some metric fasteners that didn't have a crossover. The smart ones marked them somehow. Done with double open end wrenches and combination wrenches where you might even cut off the ring end as it wasn't a match for the open end anymore. Now someone will say why not just buy metric? Well we had SAE already and it was cheaper to pickup some more SAE at a pawn shop or a garage sale than to buy new metric wrenches. When we did buy new or used metric sometimes we would just fill in the holes where there wasn't any good crossover.

[@thumbsup9208]

That's what I was looking for. Thanks for sharing

[@azurplex]

BTW the numbers and line segments on the heads indicate the strength of the material with the lines (or lack of) being SAE grades and the numbers being Metric grades.

[@belleray2]

Very helpful. thank you. I now know why mechanics continue to wreck my transfer case plugs. They are using 3/8" instead of 10mm.

[@gfrank8331]

Ty for this video not everyone was taught this

[@michaelkulman7095]

Excellent video! People miss that some substitutions only work in one direction. When I was young few had metric sets and as foreign cars became more common we made these subsitutions and even picked up extra SAE wrenches in some sizes to file down the open end to fit some metric fasteners that didn't have a crossover. The smart ones marked them somehow. Done with double open end wrenches and combination wrenches where you might even cut off the ring end as it wasn't a match for the open end anymore. Now someone will say why not just buy metric? Well we had SAE already and it was cheaper to pickup some more SAE at a pawn shop or a garage sale than to buy new metric wrenches. When we did buy new or used metric sometimes we would just fill in the holes where there wasn't any good crossover.

[@petemoore8923]

I love hearing stuff like that. I work in a fab shop that has a dinosaur toolbox that belonged to god knows who before we moved in. I dig in it all the time. A LOT of modified wrenches in it.

[@michaelkulman7095]

@@petemoore8923 Carry weight was also a factor for some as carrying a full set of sockets and wrenches in SAE and metric is a big deal. Later I bought a set of Metrinch to address that...

[@mrrobotto3321]

thank you, I just printed the PDF to put somewhere in my tool box.

[@HartzHomestead]

I use mine quite a bit, printed on cardstock.

[@j.p.8095]

Sir you r the best, thanks for the charts! Great work

[@abdelazezali8612]

Very Informative, Thank you.

[@NigelGraham-k6u]

this is great

[@serenakoleno9338]

Great video. Saves us time and money. Thank you.

[@Musical_Magpie]

I purchased a Fiskars reel lawn mower that needed its handle attached. I was provided with four 8.8 mm bolts. My lovely socket set has a comprehensive collection of sockets in both metric and inch sizes - but do you think I could find a match? A frustrating internet search for a simple answer to a simple question finally led me to this video. Thank you so much for your straightforward explanation and handy chart.

[@maddalab]

Great video both the quality and the narration. You should do more videoes.

[@HartzHomestead]

I agree, I should finish more videos. I have several partially done, but the editing is very time consuming, and life is busy. Also KZbin is unpredictable and I've put huge amounts of time into videos that barely get seen, which is discouraging. This one happened to hit on a topic a lot of people need.

[@maddalab]

@@HartzHomestead A family member of mine has a channel and has done a few videos and taken a course. The algorithm biases towards promoting content from channels that post regularly. Twice a week is what it seems to like the most I believe. But as you say the video editing does take a lot of time and results can be unpredictable. Good Luck tho.

[@PatJones82]

Great Video and thank you for the chart!! Very helpful. :)

[@Sweshification]

This is sooooo helpful, Thank you!

[@xx9mmskeeterxx174]

I just want to bring to light that sure both a metric tool and standard tool might "fit" a bolt, nut, etc but its the one that fits tighter with less slack that is the correct tool.

[@michaelkulman7095]

Actually sometimes the substitution actually fits tighter...

[@seanjohn2381]

awesome thank you. I also printed out the pdf file to put in my tool box

[@ROMANEMPIRE69]

Thank you for this amazing and informative video. Based on what I just saw I’d rather go ahead and get SAE in addition to my metric set of sockets and wrenches. Trust me I’ve had my “fun” with nut and bolt slippage. I’d rather get the correct fit. Also because i enjoy my tools even it’s just to pull out my tool box and look at the shine. 😜

[@HartzHomestead]

It's pretty hard to get by in this world without a set of both, at least here in the US. As an example, my camper jack bolts are SAE, but the propane fridge is made in Sweden, so it's all metric.

[@lewischacon6009]

Loved the video very informative sir.

[@ShawnWeekly]

Amazing. Thanks for this video.

[@kaecake9575]

My instructor which is a mechanic told me this has to do with centimeters and Inches. The measurement we use today called “foot” is 12 inches long and was actually the length of King Henry I's foot - many people don't know Europeans are relatively smaller before "The New World" was discovered. Thus creating a different aspect of measurements. Im so glad 1960's and 1990's Chevy vehicles aren't so congested in measurements. This is a great video:]

[@Musical_Magpie]

you have the right idea but the wrong facts. In the 12th century, King Henry I of England fixed the yard as the distance from his nose to the thumb of his outstretched arm. (Today it is 36 inches.) The "foot" has been many lengths over the ages, as the precise length of the average foot size changed over the centuries. Only recently has 12 inches been the official foot measurement, and we have the Romans to thank for it. They based the measurement on the foot of the reigning Emperor! This varied from 11.64 inches (Emperor Maximilian) to 13.15 inches (Emperor Nero Drusus) and was finally rounded off to 12 inches - thus the "Imperial standard" was born. The Roman soldiers marched in paces, which were the length of a double step, about 5 feet; 1,000 paces was a mile. Today, a pace is the length of one step, 21/2 to 3 feet. www.factmonster.com/math-science/weights-measures/origins-of-measurements sparkfiles.net/foot-whats-special-12-inches/

[@yuvipanda]

This was very helpful to me! Thank you

[@salvaged_wretch]

As a diy/handywoman new to this … it’s all so mind blowing. Seems like this could’ve all been simplified… but then, where’s the money in that ?? 😅 Great tutorial nonetheless.

[@HartzHomestead]

The problem is these 2 systems developed independent of each other, so they are unrelated, and all we can do now is figure how to convert them. Metric is about as simple as possible, but imperial was too ingrained in the US already.

[@cristianbautista3837]

I have a 91 honda crx Japanese do you know if i should use metric?

[@HartzHomestead]

Yes, I believe all Japanese cars are metric.

[@patgarry493]

I needed this. Thank you.

[@Jsantosishere]

THANK YOU DAD I never had!

[@ATrainAC]

Appreciate you for this tip. Very helpful.

[@InverJaze]

Pet hate on cars is having a mix of both metric and imperial. Sometimes though having both sets of tools, does help when rust has reduced the size of a bolt or nut head.

[@HartzHomestead]

It does complicate matters. Car makers seem to do whatever is easiest for them, not the mechanic who has to figure out how to fix it.

[@hoffmanxgunnar]

And this is why I bought a full metric cause you can use most metric on standard and not so many standards on metric so if you only get one get metric

[@HGEntertainmentTV1]

Thanks for the info. Learned now..

[@capoman1]

Hmm. I've found 3/8 to fit 10mm, ans 7/16 to fit 12mm, 13mm fit 1/2, 14mm fit 9/16.... I'm looking for a 18mm equivalent as many kits leave this out for some reason.

[@JorgeGironUPCI]

Thank You! Sir!

[@ValeriiAS]

very useful, tahnks!!

[@thereviewer4173]

Good video, but using some of the wrench sizes that you call similar can have you fighting the wrench because now it’s stuck to the nut or bolt.

[@HartzHomestead]

Yes, it's always best to find the wrench that fits best. But if you don't know if it's metric or SAE, this may help you find the right one. Also, everyone doesn't always have a complete set of both.

[@petersamodhar9527]

Please please, make a video on b. S. W. Spanners old and new types.i would be greatfull to you.thankyou.

[@HartzHomestead]

Sorry, that's not something I have any expertise on. The information must be available somewhere on the web.

[@tommurphy9278]

Thanks for the chart comes in handy.

[@HartzHomestead]

You're welcome! I agree, I made the chart for myself first, and use it quite a bit. Glad to share it with you.

[@HWCapps]

Thank You I needed that

[@jg1468]

Can I use metric sockets on standard bolts or will I need a standard sockets as well?

[@HartzHomestead]

Some sizes are interchangeable, others are not. You can get away with a complete metric set plus a few standard sizes that don't have good metric equivalents. The most important are 3/8", 1/2", 9/16", 11/16", 13/16" plus you might want 1/4", 1" and 1 1/8". If you run into standard very often, you might as well have both sets.

[@My2kClipz]

So 1/2 is a 13mm correct?

[@HartzHomestead]

Actually 1/2" is smaller. 13mm is 12 thousandths of an inch bigger, which is quite a bit. So if the bolt or nut is a 1/2", the 13mm will fit pretty loose. That might work OK if it's not very tight, but you could strip it if you have to apply a lot of force. If you can get a 1/2" on it, that will fit tighter and be better for the bolt or nut.

[@My2kClipz]

@@HartzHomestead I was removing my car batter the washer holding the screw needed a 13mm a 1/2 wrench got it off I will put it back on tomorrow and let you know how it go thanks a lot tho this video taught me something

[@Kyle5K]

Thank you!

[@GHE2005]

Great! Most helpful.

[@nelsonthekinger]

Thanks for the video!

[@hakimhlm4084]

thank you, you help a lot my friend 😇😊

[@snugzillal]

Hello was wondering if working on a Chevrolet vehicles if you can use Metric measurements without damaging the bolts

[@HartzHomestead]

American vehicles, including Chevrolet, have been almost all metric since the 1990's, so unless you have a 1980's or earlier, it's rare to find a bolt that's not metric.

[@Walkercolt1]

MOST SAE to Metric conversions are APPROXIMATE and are "sloppy" fits. A six-point socket will USUALLY hold while a 12 point will USUALLY slip. I have 62 year-old scars on my hands to PROVE IT. The fancy "grip-end" open end wrenches usually hold very well. Use a ratchet with an extension with a socket to save your knuckles, if it slips.

[@HartzHomestead]

That's why it helps to know exactly how much difference there is, and which is smaller, a lot of info to keep track of. A 5/8" wrench is .005" smaller than a 16mm, so if you have a 16mm nut, a 5/8" wrench or socket will probably fit, and be tighter than the 16mm and less likely to slip. I've even used a 1/2" wrench on a 13mm bolt, which was a very tight fit, as the 1/2" is .012" smaller, which is a lot. What you're talking about is when people do it the other way around, and try to use a 13mm wrench on a 1/2" bolt, which is asking for trouble.

[@AlRHORN]

Very useful, thank you

[@lithunsaravanan2784]

Super explanation

[@1marcelfilms]

I wonder how well a 3/8 will do on a rusty rounded 10mm

[@ArtofSilkPainting]

If you can get it on there, maybe file the 10mm down flat on 2 sides, otherwise lubricant and vise grips.

[@dutchleussink156]

Thank You Sir.

[@kingduckford]

I drive several 1980's Fords, so I must have a full set of each Metric and SAE. That said, my experience is ALWAYS use the proper socket and NEVER use one that is "close enough" because that IS how you strip stuffe. Better safe than sorry, because you know just how fun it is to take out a rounded head bolt....

[@rickeyezell9136]

1 3/4 sae versus what size mertic

[@jackmoran6045]

Ford and Chevy trucks still are not 100% metric

[@HartzHomestead]

Good to know. Not surprising.

[@paulg444]

great video, are there any practical near equivalences between SAE bolt and thread pitch and metric thread pitch, for instance is 7/16-20 practically equivalent to M12-1.25 ?

[@HartzHomestead]

Perhaps someone else has a more knowledgeable answer, but in my experience if a thread pitch isn't identical it probably won't work in most applications.

[@paulg444]

@@HartzHomestead That is my experience too.

[@NigeriaFunk]

MANY THANKS!

[@CaLiRr-of6ur]

Thanks , that will be useful.

[@adrianotrack9258]

Good vídeo

[@Jayreek]

what tool do I need for a 8.8 bolt plss tell me I need it for my gokart

[@HartzHomestead]

The 8.8 only tells you that it is metric of a certain hardness, not what size it is. You need to either measure it with a metric ruler or try different metric wrenches on it to see what size fits.

[@Jayreek]

@@HartzHomestead I found it it was 10mm but if its hard and hard to move its the right wrench right it fits on the bolt

[@ninjagamer4515]

What is size larger than 9/32

[@HartzHomestead]

The next size bigger than 9/32" would be 5/16" or 8mm, which are almost identical.

[@wytchypu7412]

fantastic!!!

[@gentlerowdy]

hi can you help us know the difference between sae & AF or they both are same ?

[@HartzHomestead]

AF simply means "across flats" so my understanding is a wrench marked AF could be either metric or standard. The AF doesn't really mean anything now days since all wrenches are marked with the distance from one flat to the parallel flat across from it. Apparently in the 1800's in Britain some wrenches were marked with the bolt size, not the head size.

[@gentlerowdy]

Than what’s SAE and AF relationship with ??

[@HartzHomestead]

That's all I know, and I found it by Googling it, because I had never heard of AF before. So try searching Google for more information.

[@TassieLorenzo]

@@gentlerowdy AF means across flats, the size across the flats of the bolt. Previously, British spanners were marked with the thread size so a wrench labelled 1/2" W (Whitworth) would fit a bolt with a 1/2" diameter and the bolt head size was defined as a mathematical function of the thread diameter (in this case .920" across the flats for a 1/2" W wrench). I.e., it was NOT 1/2" "across flats". Therefore the markings 1/2" W and 1/2" AF allowed you to tell the two different types of spanners apart. SAE and AF is the same.

[@srinivasarao336]

thank you

[@noahriding5780]

When you go to say drill a hole to put a bolt in, are you supposed to put the bolt size to the same size of drill bit for the hole? Or do you actually want the hole to be a size bigger, so that you can work with it if you need to get it out? (And is that different in woodworking compared to metalworking?)

[@HartzHomestead]

Depends on how tight you want the bolt. Usually I would drill it exactly the same size, in either wood or metal. Unless a bolt is heavily galvanized, it will go in and out easy enough. For a tight fit in softer wood, I might drill a little smaller and drive it in.

[@noahriding5780]

@@HartzHomestead Thank you very much!

[@6atlantis]

If I can only afford one set should I buy SAE or metric?

[@HartzHomestead]

I'd get metric if you'll mostly use it for vehicles, unless you have very old US vehicles. In the US for construction bolts or yard tools you might need SAE. If you get a metric set plus 1/4", 3/8", 1/2", and 11/16" that would cover most situations, also possibly 13/16", 1" and 1-1/8".

[@6atlantis]

@@HartzHomestead thanks

[@Eve....747]

Hi, I've got a bolt 🔩 with a marking 8...does this mean a grade 8 bolt in strength, bit confused 😕, what I thought before than now watching this video...the bolt is for a YAMAHA xj900s diversion suspension bolt... as I'm searching the meanings, basically bolt has seized onto frame, so will have to cut suspension away, then leaving bits of bolt stuck to frame, hopefully thy just will pop out!? 🤔, after major surgery or will have to drill out....as it's like this video is showing spanner size, which probably is true in meaning, though is the 8 on the bolt also meaning grade 8 strength... Kind regards Pete... 👍

[@HartzHomestead]

A number like 8 on the head usually means it's metric. An 8.8 is equal to grade 5. An SAE grade 8 bolt would have 6 radial lines, so it's likely not that. Yamaha is probably all metric. Sounds like you might have to drill it out, or use a screw extractor. I assume you've already soaked it well in penetrating lubricant, used an impact wrench or hammered it a bit, and tried heating around it with a torch.

[@Daniel198549]

Very helpful

[@world_still_spins]

Which companies make half sizes in metric? Like 20.5mm, 21.5mm, etc.

[@HartzHomestead]

I don't know. I've never heard of half metric size tools.

[@world_still_spins]

@@HartzHomestead Well hopefully some manufacturer turns it into something known. The amount of times I had as a mechanic and construction worker that neither SAE or Metric would fit a bolt/nut/fastener correctly, a half size Metric wrench/socket would have been helpful. (Yes there are obscure fractional SAE sizes such as 13/16" 27/32" 53/64", but remembering those can be a headache.)

[@HartzHomestead]

Actually, that's a brilliant idea, because metric is so logical, and that would cover most standard sizes that don't have an even metric equivalent. You could even get away with fewer standard wrenches.

[@michaelrobinson2528]

Awesome Video. thanks

[@VODZ]

Awesome!

[@far06c]

Great video!!! Thanks!!

[@STARBOYGODD]

great video

[@Cheapass_mx5]

Thanks very usefull

[@henriks5008]

No need for charts. My dad has some imperial wrenches in his garage. I remember using them when I was a kid, and I always just used the one which fitted the nut best. Never rounded a single nut or bolt.

[@HartzHomestead]

Whatever works!

[@angelafox4380]

Why is this so confusing to me?? Lol. Thank you for sharing.

[@HartzHomestead]

Well, they are 2 completely different systems, so one way to compare them is to translate both into thousandths of an inch. If numbers aren't fun for you, it's a lot to take in. I've always loved numbers, so for me it's like a mathematical puzzle.