Casio fx-991CW– Advanced Scientific Calculator with High-Res 4-Tone Display | Natural Textbook Display | 540+ Functions, Numeric Calculus, Matrix Solver | Ideal for Engineering, Science & Exams

The Casio fx-991CW is an excellent calculator with very good performance and a wide range of useful features. It is easy to use, fast, and well designed, making it perfect for students and professionals who need reliable calculations. The display is clear and the overall build quality feels solid and durable. I also want to highlight that the Amazon delivery time was reasonable, especially considering that this was an international transaction. The product arrived well packaged and in perfect condition. Overall, I am very satisfied with this purchase and would definitely recommend this calculator.

Great calculator, easy to understand, amazing functions, im uding it fot mu physics class and it is perfect for it.

I received this calculator in perfect condition, and after using it for several months in a very demanding master’s program, I can say it works flawlessly. It’s reliable, fast, and hasn’t given me any problems at all. For anyone who needs a solid calculator for advanced studies, this one does its job extremely well.

Great quality and sleek design.

I bought this mostly to see the difference between the fx-115es+ which I use at my desk. I like some of the pros, but there are a few big cons. Compared to the 115: Pros: 4th deg polys and 4x4 systems, a bit easier to navigate, handling variables (see them all at once, pick and assign) and stat output is much much simpler to see (just see it all at once instead of picking single values from the menu to see. Cons: Way fewer things on the keyboard, including some fairly often used ones like the exponential (to compute e^2 now you have to press shift, 8 (e), []^[], 2). Then they put 3 different logs on the keyboard with the general one in the unshifted position. Way more sensible on the 115. Some keys don't even have shifted variants. And some things just have way too many ways to be accomplished (while some things you have to use the menu for compared to the 115 as if we're missing room on the keyboard). E.g.: There are two ways to type x, 4 ways to type 1/9 (you could use the division bar, the divide button, you could use the ^-1 key and the general power key with -1. So we're getting all that but no quick way to write the exponential and the natural log is under shift? OK, some of these are also on the 115, but at least I don't feel like the useful ones got hidden there to make room for many ways to do one thing. Some keys don't even have shift variants, as if you really should just use a menu for everything. Then a bunch of features are missing for some reason. There is also the rather pointless QR gimmick eating up another space on the keyboard. That could have been in a menu given how few places it comes up even if one would want to use it. The final and huge con (though the 115 suffers the same thing to some degree) is that history gets erased when 1) you change modes, 2) you press "back" one too many times (that is infuriating and annoying as you use "back" in menus) 3) When you press "home". What's more infuriating is that they added "undo" where it is not needed, but you can easily erase all history by just an errant keypress, it's almost like rubbing it in your face. 115 does the same thing, but because of the lack of the back button, it's less likely to erase history by mistake. Also, why is there still a separate complex mode. What's the point. Why not just handle complex numbers in the main compute mode. That just doesn't make sense to me. This way you have to And why does it still not handle complex exponentials and trig functions, I mean it's so easy to implement. Overall, it's easier to use than the 115 in some aspects, but the downsides are also quite bad. It's kind of a meh. Given a choice I'd pick the 115, though there are a few things I really like about the 991CW (like the variable menu).

My engineer husband loves it!

Works great, was very helpful on a recent test, has many functions like it says it does, so I would recommend to this to anyone looking for a cheap good calculator.

A semester in the calculator works well, buttons are tactile and responsive. The main quality of life improvements u notice is the surd function and fractional answers, the fact u can modify the display to suit ur eyes, accuracy is a plus and its durability. The calculator interface is refreshing, readability is eased . Its great value given the graphing function although accessed through ur phone on a website with the QR. The school use is exceptional, and relevant to my Pre Engineering classes and would be using it for my further degree. However in exam time they did call my casio calculator a semi-programmable, had to pull out my sharp and dust off the codes and functions I memorized. The examiners allowed the older model casio class Wiz which is more button oriented than this one which is screen oriented. 🤔 given a university scenario I did have my doubts on that exam certified. If anything I'll invest in the older model casio class wiz. As well