Casio FX-991EX Scientific Calculator Review

Casio FX-991EX Scientific Calculator Review
Footage taken from EEVblog Mailbag video #787

[@blacksmoke9495]

Watching this on my casio calculator

[@Crazytesseract]

I am sorry to say it, but you are speaking the untruth.

[@GB_B]

Me too!

[@yeety1208]

Watching it on my ti nspire

[@Spiderman-tz7xs]

Hehe

[@soadhossain7068]

😂😂

[@LazerLord10]

I honestly wouldn't mind you going through a lot of the features on a calculator. I'd definitely learn something.

[@bobbythebobtail]

edu.casio.com/forteachers/er/movie/howto.php Here you go - videos for all the features

[@AhmedAbdullah-me5xb]

@@bobbythebobtail thanks

[@Veptis]

The best feature is variables. Go into menu 1 and then write something like ax^3+bx^2+cx+d and then press CALC and it prompts you all variables, so great and so easy. It also remembers.

[@adam79634]

the equal button works like an enter in the menu

[@tarunmistry5204]

adam adam i just came here to say that. Also im surprised its hard to get in the uk they are super easy to find

[@joshuathompson7333]

Tarun Mistry yeah you can also get em in Argos

[@harrym1862]

@@tarunmistry5204 I've got the 85gtx which is practically the same

[@wilbertbirdner1303]

oh look, it even have wireless power capability!

[@LazerLord10]

Idea for filming future calculators: Have a separate view of the screen where it's the same video feed, but just zoomed in. I imagine that you could just have the keypad off to the side or something.

[@Manawyrm]

I got this calculator when this mailbag video originally came out and have since used it at my HAM radio exam, it has been extremly helpful. Great tool and excellent value.

[@theboots39]

I teach HS Math here in the states and I'd never used a Casio calculator until I picked this exact model up on a whim a month ago. So glad I did. I love the thing, and I started recommending it to my students. At $20, it renders their school-required TI-8Xs pretty much obsolete (except for graphing). Only thing I hate are the slippery plastic feet.

[@ronrestaino8182]

Use the table function and make your own graph.

[@MrFrazierNation]

2 years later, Dave, and you made the decision for me simpler. I was after a TI Nspire CX but for $15, IT CAN't BE BEAT! I lost my previous 2, so hey, need one. You are definitely right as well, having a calculator at hand beats phones and laptops anyday. I guess coming from an engineering / math teacher that's not news :)

[@ColbrelliAdamsVideos]

What a great calculator! I ordered mine after seeing the Mailbag video a couple of years ago and I've used it every day since.

[@Michael-Sasser]

In Germany, we have the FX-991DE X model, which has a few more functions and is available for 3 years now, I think. It costs about AUD$25 locally. I love this thing and use it every day. But as you said, it would be verry nice to have the engineer symbols right on the numeric pad.

[@uzmeyer1752]

I was confused when he said it was all new because i had the dex for a long time and i love it but i don't like the layout as much as on my old ti 30x, especially having to use shift for recall and pi. Also that it doesn't have persistent history memory. Still, it's unbeatable for 20€

[@florianoberacker6500]

I also love this calculator. The FX-991DE X is the standard for "non-programmable" calculators at our university.

[@physx_yt1062]

As far as I know, that's just a region specific model with German language. Are there any other differences between this and that too apart from the language?

[@Some11]

Löse mal bitte eine Gleichung und lass Dir den QR-Code anzeigen.. ist da dann auch alles schwarz ?? meiner ist Buggy an der Stelle.

[@akino_germany]

Du kannst mit dem Steuerkreuz den Kontrast einstellen, dann wird er sichtbar.

[@ezravermeulen901]

Used this one for over a year now, it's absolutely good! It is well available at my school in the Netherlands.

[@simaspudziuvelis8249]

It does have an enter key! It's the "equals to" button. I've had it for a few months. It is an amazing calculator.

[@davidgriffin79]

I remember having fun solving ODE's numerically (Euler method, was the best it could do, if I remember rightly) on a Casio calculator back in 1994 (can't remember the model number); it was fun watching it chug through the iterations to get to the solution.

[@fourtwozero]

I actually love the white/black combo!

[@GNARGNARHEAD]

cheers, I've been tempted by these for months

[@ewsclass6679]

in the UK the FX-991EX is the standard calculator in my college for A level Maths now

[@andreiarg]

Teachers recommend this calculator for GCSE too but it's still mostly FX85GT

[@deadpan8270]

FX-82 MS is the standard calculator in my school IGCSE

[@user-uq1fq6gs3i]

KaputPictures // This calculator is not needed for gcse at all. I did maths and further maths in gcse and didn’t need this amount of features. I would have this for a-level or engineering

[@Keduce22]

I still love my fx-991ES PLUS from 2010 ... I have the fx-82ES as well. But my fx-991ES has served me well through out school, A-levels and university. Funnily in my honours (graduate) year I was using both and Matlab in an exam (we were allowed to due to the number of calculations we had to do). The irony of using an old school calculator + computer software together because Im faster on a Casio than coding it all up

[@DivyanshMMMUT]

You can push (=) to select from the highlighted function from the menu!

[@NarimaanV]

Computer Engineering student. Needed a calculator that could natively do complex/imaginary arithmetic for my AC circuit analysis class and this thing saved my bacon! Fantastic calculator. Likely even allowed on FE/PE exams (the exams you have to take in the US if you want an engineering license to work as a standalone engineer) since the Casio requirements are just "FX-115 or FX-991 in the model name". Only complaint is rare glare at certain angles, and it slides off angled surfaces way too easily since the standoffs molded into the lid and base are just smooth plastic.

[@SproutyPottedPlant]

It looks so cool! Wish I was good at mathematics so I could take advantage of it's features.

[@AK-dm1kt]

I actually have had this calculator for about 6 months. I got it in a regular russian electronics retail store (official release, with a sticker that it's approved for the russian Unifed State Exam). I boughr for an upcoming physics exam and it does everything that I need, although I'm not really fond of their new design. I was really surprised when you told that my calculator just came out.

[@chrisgreece52]

Best birthday gift i got for myself this calculator. Amazing for everything involving engineering calculations.

[@Mr.M1STER]

I just bought this calculator recently. I am a die hard Sharp calculator user but everyone in my class at college seems to be buying the 991EX so I decided to purchase one to play about with and see what the fuss is about. Straight out of the box I don't like how the slide on cover fits over the front of the calculator when you would be putting in your bag or whatever it seems to stick out a bit. I also really hate the way it does not retain previous calculations after you turn the calculator off or hit the "on" button while using it, it just wipes all your previous calculations. That is what I love about the Sharp. It will retain previous calculations for ages, one time I didn't use my calculator for 2 weeks and my previous calculations were still on it when I went back. I will still use this Casio from time to time and I might grow to like it.

[@fr0nage]

The engineering units is a good idea, hopefully in future revisions they make it more streamlined to use

[@iDrinkYourMilkshake]

The thumbnail makes it look like they are going to murder the calculator

[@Veptis]

The table is great, as it does allow to add a increment with a simple + or - hit instead of add row and manually enter something.

[@09klx250t9f]

HE TURNED IT ON, AND DIDN'T TAKE IT APART O.O

[@racingmars]

You mentioned you're not sure if it's available anywhere but India... I got mine here in the United States about a month ago, it's widely available here. $19 on Amazon with free Prime shipping, even!

[@EEVblog]

This is an old video, look at the description

[@stephenwabaxter]

£15 from Amazon UK.

[@alonser1]

EEVblog jun 7, 2018

[@TheCalculatorGuide]

Excellent review and good quality camera. Picks up the details nice and clearly. You can navigate to the selected menu and press = to select if you wish to select that rather than the number....Personally I prefer VPAM lol

[@Daswarich1]

I only used the old style calculator input for a few months and never got the calculator to do what I wanted. Only issue I have with the new X variant is that you have to press shift to recall values. Oh, and it has been available in Germany for a few years.

[@zukaro]

I literally just bought this calculator a few weeks ago in preparation for university. It was one of the few they allow on tests according to their website. :p

[@dgm2006]

I love that new calculator. It’s my favorite everyday user, although I was brought up like you. Every kid should have one. But when you get older those small exponents are harder to read than on the older model when you need reading glasses or bifocals. Still I put up with that.

[@muhammadtanvir5298]

I’ve bought the same model from an authorised seller at Dhaka, Bangladesh. The look and functionality are nice. It took 1500 BDT or around 17.9 USD.

[@mmbb001]

New Casio and just been released.... I bought it 2 years ago in Hungary. Exactly the same :D

[@zer0b0t]

I think that eventually the "menu setup" button will migrate to the middle of the selection buttons. Casio should minimize the error messages by allowing the old input method, all they need is to do is to autocorrect into the "visually perfect" method.

[@TingFeng77]

If by old input you mean like typing 1/2(could not find the correct symbol in unicode) for fractions instead of the fancy template, you can go to setup and select input/output and select LineI/LineO and it will be like a MS series calculator

[@mikesradiorepair]

I have been using this calculator for quite some time now and it is a great calculator. It's not a HP in build quality but for the money you can't beat it. One thing to be aware of is a trap that many calculators have, this one included. Doing something as simple as 6 divided by 2 times the sum of 2+1 you can end up with two different answers depending how you input it into the calculator. Input as 6÷2(2+1) you get the incorrect answer of 1. Input as 6÷2x(2+1) gives the correct answer of 9. Input this either way in another calculator like say a HP35S and it gives the correct answer of 9 both times. Just something to be aware/cautious of when using some calculators. This is something I check on every calculator I buy so I don'g get caught in the trap.

[@ge48421]

MikesRadioRepair Casio consistently treats an implicit multiplication differently from an explicit one. 2/3x is treated as 2/(3x), and 2/3*x is treated as (2/3)*x. The fx991ex will rewrite the expression to make this clear. The Casio graphical calculators do exactly the same thing. The HP Prime acts differently but it does rewrite the screen to make that obvious. The HP35s does not accept this type of expression in algebraic mode. BTW: the build quality of HP calculators isn’t what it used to be. Which, considering the current price levels, is not that surprising. The original HP35 went for $395 in 1970 (about $2400 in today’s money) The current HP35s goes for $60.

[@Amitjha406]

if you go by the rule of BODMAS ,both answers are correct in first situation.

[@damny0utoobe]

I wouldn't say this is incorrect. You're supposed to perform the 2(2+1) first.

[@Crazytesseract]

@@damny0utoobe that's right

[@urnoob5528]

1 is the correct answer smh

[@moccaloto]

Take a look at the DEX version. You can order it from many EU stores. For instance amazon DE, etc.

[@christopherkise]

Available in Norway, has been for at least a year. Standard at my school, and I like it, not as much as i like my old ti-84plus , but the equation is so much easier on this one. I do find that i would have loved to have the display tilted just a mm up on the top. Not wery easy to read the display from the table when just punching in stuf. Needs to be hold in the hand to show a good image.

[@okaro6595]

Does this have the annoying feature that when you press a function like sin or square root, it will add the parenthesis and you need to close it? For this I prefer by fx-115W even though it lacks the multi line call back.

[@djslaviero]

Got this same model, really like it!

[@MatthewSuffidy]

I rooted a sony e reader and installed virtual ti (89) on it.

[@prestonferry]

Just released? I thought it was released in 2015?

[@Peppermint1]

I felt off my chair when you pulled your 'swiss knife'. When you do a simple addition on these, such as 45+234+345+232= does it show all the numbers at same time on the screen, each number on a different line?

[@Popart-xh2fd]

I have that one, the blue color on the dark surface isn't easily visible under low light conditions!

[@faxezu]

I have a Casio FX-991DE X, it is the same calculator only with german menus. So it is available in other countries but may have a different model number. Edit: The left arrow works as a backbutton and = as Enter.

[@simontay4851]

But does it have functions for ohms law calculation and other electronics formulas or do you still have to calculate them manually? I have electronics applications (electrodroid for example) on my phone and tablet but a dedicated device with real buttons that has the same or similar features/functions would be much faster to use. Its instant on and I wouldn't need to load an application.

[@EricBrunoTV]

Please How to calculate (a+b)^n ? For example (a+b)^3. Thank you

Does anyone know if this model can solve system of equations with complex numbers? I couldn't fild how if it can

[@marka.200]

Got one off Amazon for $18.32 US today. Sweet!

[@abhiramshibu]

U can so press = to select U can also put it to line output and it will be like old calculator

[@nagasainathkoduru9995]

It is basically for engineering students We use it a lot to solve problams in exams Its perfect for our use

[@tech29X]

New? Where you been mate, under a rock? It's been out and available since 2015.

[@nrdesign1991]

The original video convinced me to get the 991 X. I'll never go back to the 991 S unless I absolutely have to.

[@cornevanzyl5880]

Does it do roots and powers of complex numbers and phasors?????

[@Ross_an_Artisan]

I purchased this in 2nd year of my engineering, best function veriable calculation

[@playerguy2]

Yeah, one thing worth noting operation input order. My old casio fx-10F (older than I am, 30 years going strong) uses reverse polish notation (RPN) the fx-991EX uses PN instead. You can either get: - used to it - a new one you decide. Just gotta get used to it. My friend complained for days about his RPN calculator.

[@okaro6595]

Neither RPN or PN. In RPN you calculate 1+2 by pressing 1 enter 2 +. Sure with functions modern calculators put the function before the operand. There are cases+ where the older system where one has always one number visible an then does calculations to it is better but overall the formula entry is better. If you eant to take a square root of the value on the display instead of just square root, you enter square root, Ans, =. In the line-io mode it is enough to enter square root =.

[@sahilgujral1110]

The 991 es also has a second gen model and looks quite good

[@rebelrebel5545]

Please give a review about Casio FX- 991 ES Plus scientific calculator.

[@0xTJ]

I've been using the 991EX for the least two years at university.

[@oreste6076]

Anyone knows a video. Who designs and how. These things. Thank you

[@AaronCocker]

Don't forget the FX991ES plus model that came between the two you show there.

[@nicksavard6819]

I've been using Casio calculators for most of my life. Most of which has been the perfectly algebraic types. I've just gotten used to the way of inputting on that type

[@deadeye8]

What are those CRO type things in back. They really got me!

[@kajyakuzonik9130]

Wish I could get that Casio with TI-85 keys (my all-time favourite tactile sensation of any calculator I've come across - the screen was a bit hard to read on the TI, though)

[@gerryjamesedwards1227]

I've got an elderly FX-7400G... it's great but maybe I should get one of these as a backup.

[@user-eh6ee2kz9q]

Do you know anybody TI-36x calculator? What will a better choice, TI-36x vs Casio 991ex plus?

[@luh.breezy3558]

For full review of casio fx 991 ex classwiz + also game you can play on this calculator + more, Please checkout my friend's video : kzbin.info/www/bejne/pnazhZWsfJx_gac like and subscribe if it helps☺️👍

[@araibirshad8294]

Its the same as the old fx 991ES.. just some changes in the UI. The UI changes unfortunately(or fortunately) make it more accessible to new students and confuses the veteran users of the old 991ES

[@joseph_donovan]

What are the other five calculators in your collection? Great video.

[@ArmiaKhairy]

This calculator is in other countries, but the name is a little different, for example: In middle East where I live the model is fx-991AR X, since AR stands for Arabic Display and it doesn't have the mode #7 on the EX model.

[@nukularpictures]

Well I got the fx-991DEX quite a while ago (about 2 years) and it looks exactly the same. I could order it directly from amazon in Germany. It is really a nice calculator. Edit: Complex numbers was so damn helpful in the uni :)

[@preetamlahre2923]

How repair it when it is not working

[@KennethRosenstroem]

10:25: "I'l link in some videos....." - OK, still waiting for those...

[@ahmadalbadri3385]

Can it do logs or it’s still only does 10

[@okaro6595]

They do not tell the power consumption on solar models but the non-solar version SX-570EX uses 0.0006 W, slightly more than the ES-model.

[@johnbecich9540]

Can the fx-991ex take the square root of a complex number?

[@ace_of_john_warrior8590]

Ohhh I just got one of these bad boys, I watched this video because I was thinking about getting it. Its so amazing

[@J.-N.T.]

the best calculator I have ever had since I study 20€ Germany including shipping February 2018

[@jamesgrimwood1285]

I'm a programmer (that other kind of engineer). Is there a physical calculator that works like those computer based equivalents? I.e displays 32bit binary in decimal, hex and octal at the same time?

[@MichaelKathke]

Maybe SwissMicros DM42. It's an improved HP42. www.swissmicros.com/dm42.php

[@simonplmondon1234]

Ti Nspire CX Cas or HP prime

[@Crazytesseract]

This one can, but you have to switch between screens, using DEC, BIN, HEX, OCT keys.

[@S1nGuLariTY_]

What is the difference between FX 991 ES and FX 991 ES PLUS?

[@fersunk]

In my FX 991ms I can access the engineering symbols just pressing shift + 1,9 and I love it. Looks a bit too much hassle doing 3 steps for that. Too much functions and you ended up with a lot of compromises of the "basic" functions. The FX 991ms is a good all around

[@okaro6595]

MS has an annoying bug that if you calculate Ans+1 and then store it into memory it will recalculate it storing a wrong value. This was a major reason I bought the fx-991EX

[@fersunk]

@@okaro6595 mmm, I don't remember the last time that I used the memory function. I write everything on paper anyway, or just in brain

[@okaro6595]

@@fersunk I constantly use memory. Memory is also the only thing that survives power down.

[@slap_my_hand]

I don't get how people can enter long formulas into regular 7 segment calculators. VPAM makes much more sense to me.

[@EEVblog]

For most everyday stuff I do I don't have to use long formula

[@Crazytesseract]

You can, but one needs a little patience and some tricks! I think people were more smart back in the days when machines could do relatively less functions. Now it is like: the smarter the machines the dumber we get.

[@The.Talent]

I’ve had this calculator for about 3! months. It’s a fantastic calculator. I added a printout list of the stored constants to the inside of the cover. It’s a little confusing navigating through the constants menu without this list.

[@The.Talent]

imgur.com/a/vjlxs21

[@Crazytesseract]

That means you have this calculator for about 6 months. 3!=6

[@tristan6509]

actually the '=' key is the enter key, they just didn't label it. You can choose the menus with the '=' key.

[@tme2912]

My favorite calculators are HP. HP prime is very intuitive. Curiously this casio is accepted for UK exams, the TI and HP are accepted in France and germany for exams but not the casio ....

[@adamskrzymowski4025]

T ME in the UK at least there aren't any specific models accepted for exams, just a list of what the calculator can/can't. However Casio calculators are accepted as the standard (even textbooks assume you have them) and are most widely available, which is why they're the most used.

[@rjcroy]

Casio FX-991 calculators (all variants) are approved for school exams in all subjects in New Zealand.

[@ahmadhasan8355]

forget the calculator. What's the price of the knife?

[@chrisridesbicycles]

Did they really drop the handy cheat sheet for the shortcuts to the physical constants? Bummer! I still use my 992s from the 90s without cursor keys an menus. Once you are getting used to it, you are much quicker with the old shortcuts.

[@nickpelov]

does it have parallel resistance button?

[@Crazytesseract]

no but you can use (A^-1 + B^-1)^-1.

[@7alken]

yeah, here in eastern EU (V4 in fact) they released "FX-991CEX" ;-) ... and may be , combined with 991EX its small step to English teaching too (math and logic is needed to teach better again, so early) ... BUT the new firmware 3.20 for FX-CG50 includes MicroPython 1.9.4, nice too ...

[@debasishraychawdhuri]

I have a 991ES-PLUS, I am planning to buy this one. Not sure my wife would approve. They could have had made it black though.

[@Upper_Room_Studios]

For the life of me, I don't know why it doesn't have a GCF and LCM button like the fx115es Plus.

[@NeverKnowWhatToPutHere]

Can you add complex numbers into a matrix? Or a complex number in the simultaneous function?

[@Crazytesseract]

No this model doesn't allow such things. You need to get hold of some programmable ones or a calculator like the old HP42S.

[@Veptis]

Needed this one for 3 years of school. Switched to a graphical one for the last 2 years of school. What I love is that you can use the various variables. Input an equation and than use CALC to calculate different variables. Table is also really powerful once you know the buttons.

[@marokmarsci3557]

It has been available in Europe for a few years now.

[@mariolenta2178]

you didnt mention the qr feature

[@GRBtutorials]

I love complex numbers too! And calculators as well!

[@Crazytesseract]

But it cannot do everything with complex numbers like for example the HP42S did. You can download the Free42 app for Android and check out its powerful complex number features!

[@MrMartinZockt]

The FX-991DE X is my daily driver and I like it.

[@monoman4083]

where are links????