Casio FX-991EX Scientific Calculator Review

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


Martin Špina says:

I wanted this beast for my study. And because I am dumbass I ordered fx-991ES instead! 😀

Christian Schneider says:

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.

MrJason005 says:

you didn’t mention all of the physics/chemistry constants it had integrated in it
also, we’ve had these in the UK for a year now

The Talent says:

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.

plemli says:

Why do asian designers so often use ugly serif fonts ?

Shakaib Safvi says:

These CASIO calculators must have some OS given the complexity of functions etc?
if they do, can it be hacked ? 🙂

May be add a few new custom functions !!!

slap_my_hand says:

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

Corne van Zyl says:

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

☣droid☣ says:

Heh, I still use my FX-115N. I don’t know how old it is but I got it new when they came out which I guess would make it around 30+ years old and still working great. Particularly handy for quickly converting between bases.

zerpBot says:

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.

Avetho Plays says:

Thing is with a multi-use device like a phone, it can never really beat a dedicated device of equal spec. A computer built to be good at everything is worse at being a gaming server than one built to host a game server, it’s worse at rendering videos than one built to render videos, likewise a phone is worse at doing calculations than a calculator since that is all a calculator is made to do, to calculate something, even to high complexity like solving an octic (x^8) equation, as fast as possible while using barely any power. Yes, a phone might be faster at the calculations themselves, but it’s not designed to calculate arbitrarily like that.

I just dumped an octic equation onto my fx-991ES PLUS C with Natural VPAM to see how fast it can find one of the roots. It was this: 0=4X^8+15X^7-12X^6+5X^5+54X^4-324X^3+1254X^2-1465X+15643. Told it to find X. After about 5 minutes of constant calculation it yielded me the first of the roots, a large 47898.05644 and it asked me to continue by hitting equals again to calculate the second of the 8 roots. My phone can’t do that. I can’t even do that on paper yet! :-O


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

Rounak Dutta says:

Shift + 7 + On… That’s the first set of keys that I press when I buy a new Casio scientific calculator.. or if I accidentally drop it… 😉

The Boots says:

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.

sageverd says:

PPS: nobody will read this long post on why calculators are overpriced and useless…but i will still post it here..

I still don’t get the appeal of this calculators…I have an old one from my fathers days in collage…and i love the green display and the tech behind it…
But i still think it is unnecessary in this era…
I have been programming industrial equipment for over 5 years and never once needed a calculator…i used the one on my pc if necessary.
I do not say that there are businesses that require a lot of computation…but using an old school calculator in 2018 seems so outdated and useless..
That being said i will always keep my fathers calculator as a museum piece since i love old tech and computing history…
But still…why use calculators when you have so many other variants…
And yes you may say that it is more reliable…even if you use titanium and make them resist a nuclear blast….the price is still 90% to large

Oreste Schaller says:

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

Nick Savard says:

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

T ME says:

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 ….

design of modern life says:

yep nice , shame my hp50g eat too many batteries , some day i will mod the thing , but hey nice casio you got there :0)

Oreste Schaller says:

Still not IoT

Claudius says:

Screw your damn phone!

AL_O0 says:

Actually it has been available for at least a year in Europe as far as I know

nrdesign1991 says:

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

Nermash says:

HP Prime ftw 🙂

The Calculator Guide says:

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

Justin Spencer says:

Shift+7+AC+ON button then pressing 9 unveils the self-test mode.

There was a hack on lower fx-99XX models that no longer work on the ES+ and this one.

Hagledesperado says:

“Screw your damn phone!” — David L. Jones, 2018-06-07

Ian M says:

But can you enter 71077345, or, more importantly 80085? 🙂

wotid says:

I hope those non compliant led drivers ( deemed prescribed electrical equipment) in your ceiling don’t cause anyone else in the corporate building you share any harm. No C tick, no RCM logo. Illegal equipment you’ve installed and substandard by your own testing.

A13tech says:

New Casio FX991EX (or any similar calculator ) cost similar as used TI Nspire CAS so why should anyone buy it ? I have TI Nspire CAS and i can’t imagine a better and useful piece of machine as it is. Why is so good ? efectivity vs price is not better than Ti Nspire CAS i think. In real life nobody needs spent time with xxx steps of derivation of equation, click click click, done… I save time and energy for later.

John Senchak / Internet & Network Security says:

OPTO-COUPLER ON YOUR SHIRT ? You can put that type of calculator on your phone ! I use to like the Casio calculators that where programmable and had graphs functionality

Marcell Boros says:

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

3k2p6 says:

FX-991ES then FX-991ES PLUS (the one I own) and now FX-991EX

Hyss says:

I will have to get one. I have to know I have every Casio calculator, and I am working towards every TI one too.

Simon Tay says:

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.

SzDavidHUN says:

We can buy it in hungary at shops for… F***ING $40! We got so little money, but everything cost more than anywhere else. People wonder why I buy basically nothing from our country.

I use computer and smartphone for everything including the kitchen sink, but for calculating things, I use calculator.
But I’m so out of money, that I cannot afford a Casio FX-991EX. 🙁 😀 :'( My current calc is FX-82ES Plus, which is good, but not that great as shown one (I’ve got is as a gift from a few years ago). Sometimes I have to use function table (you can enter a function, and the calculator will calculate up to 30 results), but with a bigger function, it needs seconds sometimes 😀

o says:

I have bought mine in Hungary for about half a year.

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