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Casio FX-991EX Engineering/Scientific Calculator, Black, 3" x 6.5" x 0.4"

4.8 4.8 out of 5 stars 18,123 ratings

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Calculator
Brand Casio
Color Black
Calculator Type Engineering/Scientific
Power Source Solar, Battery
Screen Size 2.5

About this item

  • High Resolution Display to view more data like spreadsheets & 4x4 matrix calculations
  • Natural Text book display - symbols and numbers appear just as they do in textbook
  • Numeric Integration/Differentiation. 552 functions
  • Simultaneous and Polynomial Solver
  • Solar Powered with Battery Backup (LR44 Button Cell Battery Included)
  • Input and display fractions, powers, logarithms, roots, and other mathematical formulas and symbols just as they appear in textbooks.

Compare with similar items

This Item
Casio FX-991EX Engineering/Scientific Calculator, Black, 3" x 6.5" x 0.4"
Casio FX-991EX Engineering/Scientific Calculator, Black, 3" x 6.5" x 0.4"
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Details
Added to Cart
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Added to Cart
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Added to Cart
Price-13% $24.49
List:$27.99
$27.29$23.99-6% $19.98
List:$21.19
-6% $32.98
List:$34.98
Delivery
Get it as soon as Wednesday, Mar 27
Get it as soon as Wednesday, Mar 27
Get it as soon as Wednesday, Mar 27
Get it as soon as Wednesday, Mar 27
Get it as soon as Wednesday, Mar 27
Customer Ratings
Easy to use
4.7
4.5
5.0
4.2
4.3
3.1
User interface
4.7
4.5
5.0
4.8
4.1
Easy to read
4.7
5.0
3.6
4.9
3.7
Easy to learn
4.5
5.0
4.3
4.3
3.5
Value for money
4.8
3.8
4.2
3.6
Sold By
The Watch Box
PRIME EXPRESS ⭐⭐⭐⭐⭐
Wefun Stationery Store-US
Amazon.com
ROATEE-US
model name
ClassWiz
FX 991ES
FX-991CW
power source
Solar, Battery
Battery Powered
Battery Powered
Solar Powered
Solar Powered
Battery Powered
battery quantity
1 lr44, 2 aa, 1 aaa, 1 product specific
1 lr44, 1 aaa, 1 lithium ion
1 lr44
1 lr44
2 cr2032
display type
LCD
LCD
LCD
LCD
LCD
material
Plastic
Plastic
Plastic
Acrylonitrile Butadiene Styrene (ABS)
style
FX-991ES
Stylish
OS 991ES PLUS Ⅱ
Portable

Product information

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Casio FX-991EX Engineering/Scientific Calculator, Black, 3" x 6.5" x 0.4"


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Product Description

Scientific calculator features a high-resolution LCD that displays more information at once to help you work through large spreadsheets, matrix calculations and more. Its comprehensive set of advanced calculations means you can work on integration and differential calculus along with vector and inequality calculations. Online Visualization Service allows you to generate a QR code for your problem, and then scan the code to immediately see a graphical representation of your data. Students can then see their collective data in real time with other students. Two-way power utilizes both solar and battery power for reliable operation in any setting. Calculator is perfect for basic math, Calculus, Algebra, Geometry, Probability and Statistics.

Customer reviews

4.8 out of 5 stars
4.8 out of 5
18,123 global ratings

Customers say

Customers like the relevance, appearance, performance and value of the computer component. For example, they mention it's great for engineering and maths students, has an appealing graphics and the button key board design is pretty sleek. They say it has all the functions they need and is very good value for money. Customers are also happy with ease of use, quality, and display. That said, opinions are mixed on readability.

AI-generated from the text of customer reviews

198 customers mention177 positive21 negative

Customers like the quality of the calculator. They say it's a great product with lots of functions and is perfect for engineers. They also appreciate the mathematical chops and ability to solve complex and imaginary problems. The statistics mode is simply the best they've seen in a calculator of this price.

"This is a very good calculator. I use it for much of my projects that require extensive math...." Read more

"This is the best scientific calculator I've ever used" Read more

"...several weeks of use, I realized that this calculator is technologically far more advanced than a fx-991ES Plus...." Read more

"...Also, as seen in the image, the Casio is accurate to further decimal points than the Ti-36x, which isn't always the best with solving integrals...." Read more

180 customers mention177 positive3 negative

Customers are satisfied with the performance of the calculator. They mention that it has many different functions to aid those studying for GCSE's or those in HS. They say it is easy to use and has all the functions they need. Some say that it helps with every class and that it works great.

"...It has all the features I need, the SOLVE function is quick, polynomial feature accepts up to 4th degree, and simultaneous equations are also..." Read more

"...3 Pro:Processor speed is nice. Definitely look into this one if you're doing a lot of definitive integrals.#1 Con:..." Read more

"This calculator is so compact, and so useful. I would pay $500 for this calculator if it was the only way to get it." Read more

"...On the plus side, this calculator is fast! I never realized how slow my TI-30XIIB was to cough up answers until I bought this screamer...." Read more

118 customers mention104 positive14 negative

Customers like the ease of use of the calculator. They mention that the buttons are intuitive, and it greatly simplifies complicated math. The LCD is easy to see and crisper, making constants and conversions much easier. It's easy to get used to, and allows you to do mathematical calculations in a very simple way. It is a good option for beginners of engineering, and minimizes inputs for evaluating formulas.

"...I am happy with the purchase. It's easy to use, and one of those things which you buy and forget, because it just works everyday." Read more

"...thing about this calculator to me, by far, is how it minimizes inputs for evaluating formulas.Example: AX^2 + BX + C -> Calc Key..." Read more

"...DISPLAY: Larger display and better shaped fonts make it easier to read. I love the icons display of the main menu...." Read more

"...had the functions I needed for grade 12 calculus class and was easy to use." Read more

76 customers mention76 positive0 negative

Customers appreciate the value of the computer component. They say it's a very powerful calculator with a lot of functionality for the price. Customers also mention that it'd make a great gift.

"...Overall, I am very satisfied with my purchase. It is worth every penny." Read more

"the best calc for the price" Read more

"...need a scientific calculator YOU MUST BUY THIS ONE trust me it’s worth every penny...." Read more

"...It is very cheap compared to other calculators recommended for college students...." Read more

40 customers mention40 positive0 negative

Customers are satisfied with the appearance of the computer component. They mention it's sleek, has appealing graphics, and has a really nice display. The button key board design is also sleek, and it appears neatly on the display. Some appreciate the features and capabilities of the product. Overall, customers are happy with their purchase and recommend it to others.

"...I really want to like this calculator. It looks great, and feels like it has great build quality...." Read more

"...The green text is OK (so this Kevlar style is OK on a calculator like fx-260 Solar II, which has no red or blue labels, but not this one)...." Read more

"...The display is roomy enough for most ready calculations and has a nice font. The calculator can do statistics, curve-fitting, integration, etc...." Read more

"...Bonus points for it looking cool" Read more

23 customers mention23 positive0 negative

Customers are satisfied with the display of the computer component. They mention that it has a clear and useful display properties. The multi-line display is great, and it is the most functional non-graphic model. The taller screen allows the calculator to show tables really easily.

"...I love the textbook display modes it can do. All-in-all, I'm happy with it and hope it lasts half as long as my still-going HP 20S is." Read more

"...cheaper fx-115ES PLUS, the fx-991EX is faster, can do more and has a better display, but unlike the less expensive fx-115, the fx-991 has no hyper-..." Read more

"...via VPAM, passing resulting to other devices, and graphing via QR code feature is very useful, and maybe unique to Casio; its equivalent capability..." Read more

"Pros1. Excellent display, very clear to read.2. Statistics mode is simply the best I've seen in a calculator of this price.3...." Read more

21 customers mention21 positive0 negative

Customers find the product great for engineering and maths students. They say it's perfect for advanced college studies, computer science courses, and engineering and scientific applications that do not require graphing. Customers also mention that the ENG and x10x keys are extremely useful for engineers. Overall, they say it is an amazing product for university students and ideal for engineering mathematical calculations.

"...Oh, and this model is also good for the FE exam and I'm sure it's the best calculator for this exam by far...." Read more

"...and Matrix operations make this calculator ideal for engineering and scientific applications that do not require graphing; and easily affordable..." Read more

"I always loved CASIO user interface. This one is excellent for engineering purposes" Read more

"Calculator works fine, great for ee students." Read more

25 customers mention11 positive14 negative

Customers have mixed opinions about the readability of the computer component. Some mention that it is light and compact, with many functionalities. However, others say that the letters are hard to see and the display is hard to read.

"...But it's not. For normal math calculations, the character font Casio has chosen is too small so all the numbers are too small...." Read more

"This calculator is so compact, and so useful. I would pay $500 for this calculator if it was the only way to get it." Read more

"...The new black Kevlar patterned style makes the dark red and blue button labels unreadable...." Read more

"...the fx-115es plus for day to day calculations -- I think it is a bit easier to read even though the screen isn't as bright -- but the fx-991ex is..." Read more

Arrived quickly, many functions, versatile non graphing calculator.
4 Stars
Arrived quickly, many functions, versatile non graphing calculator.
Arrived earlier than expected, although the packaging had some marking and wear on it. Calculator had the functions I needed for grade 12 calculus class and was easy to use.
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ALEJANDRA ESPINOZA MORENO
5.0 out of 5 stars EXCELENTE
Reviewed in Mexico on January 8, 2024
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Amazon Customer
5.0 out of 5 stars Muito Bom!
Reviewed in Brazil on May 22, 2023
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Nicolas
5.0 out of 5 stars Excellent quality and performance
Reviewed in Germany on August 20, 2023
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Jaap
5.0 out of 5 stars Perfect voor elektrotechniek
Reviewed in the Netherlands on April 13, 2023
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G.
5.0 out of 5 stars Très bon rapport qualité prix
Reviewed in France on March 19, 2023
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