Casio fx-115ESPLUS2 2nd Edition, Advanced Scientif

Solid, durable, easy to use
This calculator is great and easy to use. Lots of functions. There are lots of tutorials on YouTube and can be a little complex, but also once you use it a few times you get the hang of it. Good quality for the money. The display is a little small and only has the two lines, but you can scroll up with arrows

Great features, visibility not the best
This is a first impression, as I learn more, I’ll add info.I chose this calculator because I needed more memories/variables for storing often-used constants for chemistry courses. It gives you the following memory/variables for quick recall/use: A,B,C,D,E,F,X,Y,M, looks like 9 memories. There are also 40 built-in scientific constants which are less easy to retrieve (shift,const then 01, 02, etc.) but might be handy (of course you can save selected ones in the memory/variables for easier access).Visibility is always an issue with calculators, both keypad glare and screen angle. Compared to a very basic TI-30Xa calculator, the Casio screen is less readable because the digits are smaller and much less contrast (blue on bluish screen vs black on white/gray for TI). As with most reflective LCD screens, including the TI, you have to get the light angle just right for maximum viewing. This is a significant problem I find because lighting varies a lot in different places. Under exam pressure, you can’t afford to misread, but it can happen too easily with these screens. But the TI is easier to read – however, it is just a one-number at a time display. The Casio shows your whole formula as you type it, so for that feature you pay a price with less clarity. With the Casio, if I get the light angle best for the display, I tend to get glare on the buttons. The TI has the same issue, but the buttons are bigger and bolder and black/white, so more readable.I chose the white model Casio to see if somehow it is clearer. The numeric pad is white on gray buttons, which is pretty, but not as readable as white on black for sure. I may get the black model to see if that is clearer (actually not sure a black model is available for this exact version).My eyesight is not perfect, so this may be a non-issue for you, especially young people. I just find that the number of hours spent calculating and reading small text is a factor, so I’m trying to optimize eye strain to a minimum and evaluate study tools in that context.Otherwise, I think this Casio fx-115ES Plus is packed with a ton of powerful features and is a great value from that standpoint.Update 9/9/2022 – a feature I miss on this calculator is the “change sign” button, which flips the result from positive to negative or vice-versa. You can multiply by -1, but it feels cumbersome. Because this calculator enters whole expressions instead of one-number-per-operation like simple calculators, you may not have as much need for the “change sign” function. For me, it is natural and I often like to see partial results as I go. So if the calculation is for example: 66 / (1 – (grams / molar mass)), it is natural for me to first calculate grams / molar mass (showing me the moles of a substance), then “Change Sign” and add 1, then invert the answer and X 66. So “change sign” and “invert” go hand-in-hand for doing a computation “from the inside out” with minimum parentheses. It is also a useful skill in case you find yourself with a simple calculator on occasion. The Casio has the (-) key, but as yet I haven’t found it more useful than the minus key. Maybe someone can explain it, the manual doesn’t elaborate.Update: somehow I missed the “Ans” button next to the “=” key. So not a single button push, but the “-” button followed by the “Ans” button will invert the sign of your answer and you can proceed from there. Also, the Ans button is needed for taking a function of your last answer, such as log(), etc. (unlike simpler calculators where log always takes log of last calculation). And “alpha” “Ans” will get you the “pre-answer”, the answer before the last answer. So there is a two-memory stack at work for the answers.Update: another real weakness of this calculator is there is no (that I know of) quick way to change from fixed point to scientific notation. This is standard on many very basic scientific calculators. You can go through a cumbersome mode shift with shift keys, selecting precision, yada, but a single dedicated key is what is needed. If you have .00612 and want to quickly see it as 6.12×10^-3 or vice versa — forget it. I think that is a serious omission, and hopefully there is another brand out there with that useful key for my next calcluator. Too bad.

It works well
This calculator was a required purchase as per my son’s math professor. It does all the calculations and functions it claims to. Decent battery life, not too heavy, not overpriced, and good readability.

Llevó casi dos años con la calculadora y jamás ha fallado. Valió la pena la compra.

Used for my maths and physics exam. Good and easy to use