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Casio

Casio FX-991ES Plus-2nd Edition Scientific Calculator

  • Based on 15,024 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Sunday, Aug 23
Order within 21 hours and 23 minutes
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Features

  • Redesigned ES PLUS series calculators featuring easy-to-understand Natural Textbook Display, Non-Programmable Scientific Calculator with 417 Functions
  • Stylish design but same function as Casio FX-991ESPLUS 1st edition, 10-digit mantissa + 2-digit exponential display
  • Basic Trigonometrical & Statistics Functions, and many more functions
  • Colour coded keypad for easy key differentiation, Simple and easy to use, Comes with new slide on hard case

Description

417 functions, Display: Natural Textbook Display, LCD (dot-matrix), 10 + 2 decimal places, Power supply: Solar & Battery, Basic Mathematical Functions, Table Generation, Base-n calculation, Scientific Constants, Vector, Basic Statistics, Differentiation, Non Graphing, Matrix, Equation, Integration, Complex number calculation, Comes with new slide-on hard case, Size (H x W x D): 11.1 x 77.0 x 161.5 mm, Weight: 95g

Brand: Casio


Color: Black


Calculator Type: Engineering/Scientific, Graphing


Power Source: Battery Powered


Screen Size: 4 Inches


Calculator Type: Engineering/Scientific, Graphing


Power Source: Battery Powered


Screen Size: 4 Inches


Number of Batteries: 1 LR44 batteries required. (included)


Display Type: LCD


Color: Black


Enclosure Material: Metal or Durable Plastic


Item Dimensions L x W: 6.38"L x 3.03"W


Brand: Casio


Model Name: fx-991ES PLUS 2nd edition


Global Trade Identification Number: 73


Manufacturer: CASIO


Item Weight: 95 Grams


Model Number: FX-991ES PLUS 2ND EDITION


Mfr Part Number: C79


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Aug 23

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

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Top Amazon Reviews

    • surprisingly nice
UPDATE: I thought the U.S. version of this was the update to this model, the ClassWiz one with menus replacing some of the printed-on functions. That is indeed an update (but maybe to the EX versions rather than, or in addition to, ES versions? Because EX versions are discontinued). But actually the U.S. version of the 991ES is the Fx-115ES. I had thought that because of its lower number, it was just a lower-grade model. But in fact it is essentially the same as the 991ES with a few more capabilities and white instead of black. I like this calculator a lot so I wanted a "spare" plus it is nice to always have one of the two within easy reach, so I got the U.S. version as well. They are both similar high quality, just different colors. I am very pleased with these calculators. Previous review: I've used RPN HP calculators for years and didn't expect to enjoy or appreciate this non-RPN calculator as much as I do. The main reason I got it was that I found a couple of lovely calculator apps for Android that I figured out were supposed to mimic the 911 series Casio, and so I wanted the real thing. It has been easy and intuitive to figure out how to use. As someone else commented, this seems to be for Indian market so you probably won't have US warranty. But the US version is totally different; you have to access many of the functions through menus and they are not printed on/above the keys. But having them printed instead of having to access through menus is much more efficient once you learn where things are. The US menu version is maybe best for people who want to use the calculator briefly and/or don't want to bother learning it (like people used to a different brand). You might have to go to a non-US Casio site to find the pdf manual for the 991ES. It would have been nice to include a hard copy of the manual but these days that's rare, and I'm fine with this because it keeps prices down. US version is now ClassWiz which sadly replaced the 991 ES and 911 EX. So you have no choice but to get a non-US-market one if you want the ES or EX (but Amazon also sells a copy-cat version of the 911ES/EX from a different brand). As far as the hardware: The calculator has a nice look and feel. The plastic is premium and nice. The upper (smaller) keys feel nicer to me, especially as a (classic) HP user. The bottom (bigger) keys are a bit squishy but that's normal for most calculators. I like that there are no soft rubber keys or other soft parts (because soft plastics often get old and sticky and gross). The case goes on and off smoothly and does not scratch the calculator. I am glad I got this calculator and I'm sad that Casio is switching to a simplified look, menu-driven, version at least for the U.S. market. ... show more
Reviewed in the United States on March 15, 2024 by Ski9
    • Great for Calculations but not for graphing
Amazing item. Quality is good. Highly recommended if you want to do calculations. It’s very good with the numbering. I am an engineering student. Everything is working fine for me. Remember, not for graphing. If you are looking to graph, this is not the product. Otherwise amazing. Highly recommended. And very easy to use ... show more
Reviewed in the United States on October 14, 2025 by MUSA MD FAHIM ISLAM
    • Must buy calculator for STEM majors!
If you’re looking into different calculators chances are you’re probably taking advance STEM classes and your teachers don’t allow graphing calculators or your SAT or ACT may not allow it. Well you’ve come to the right place because this calculator works wonders. I know it might sound odd at first but as someone who’s finishing up an Aerospace Engineering degree I can say that this calculator has come in clutch in more ways than one. Whether you’re solving advanced physics problems, math, or science related problems this calculator has an application. All the different modes that come in this calculator will be able to assist you in many ways. It’s easy to use and understand, simply playing will the calculator will show you just how powerful it is. It’s great quality and the value for the price of the calculator is very worth it. ... show more
Reviewed in the United States on August 25, 2024 by Adrian
    • Calculator
Value for money Responsive Easy to use Very functional
Reviewed in the United States on June 10, 2026 by Brookline J Sarker
    • Great for those who struggle in STEM
If you're seeking a calculator that's easy to use and provide conversion sheets of different scientific units, this can be a great help. I love how simple Casio is when it comes to plugging in formulas and equations exactly as they're typed or written from your classes. It's best to take a few minutes to understand all the basic functions of the calculator because trust me, it will save you more often than you think, and helps cut down significant time from crunching numbers. ... show more
Reviewed in the United States on May 6, 2026 by ArcticTropic
    • Okay calculator, some hexadecimal support
I specifically bought this calculator because it supports hexadecimal calculations. It does but I had trouble with some calculations (I don't think it supports bigger numbers (32-bit)). Its an okay calculator but not as good as Window's Programmer calculator.
Reviewed in the United States on November 21, 2025 by Chris Pawlak
    • Excelente
Review Image by jose david
Review Image by jose david
Review Image by jose david
Review Image by jose david
Review Image by jose david
Buena calculadora
Reviewed in the United States on July 9, 2026 by jose david
    • ❤️
Casio for life ❤️
Reviewed in the United States on June 20, 2026 by Ziyad

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