fx-991EX - Casio Calculators

fx-991EX Advanced Scientific Calculator

Our advanced scientific calculator, the UK’s best selling, has natural maths display and a host of maths functions.

You get all the basic maths functions plus equation and inequality solvers, probability distributions, complex numbers, matrices and vectors.

You’ll like:
• natural maths display
• advanced maths functions
• the high resolution display
• solar power – never run out of batteries

New ClassWiz coming March 2023. Discover more.

Our advanced scientific calculator with solar power comes with additional functions for solving equations and inequalities; calculating probability distributions; complex, vector and matrix arithmetic; base arithmetic and conversion; and a spreadsheet.

Suitable for and permitted in exams where a calculator is allowed at all levels up to A-level (including Further Maths).

CALCULATION: arithmetic, trigonometry, logarithms, exponential, hyperbolic, equivalent ratio, complex number, vectors, matrices, base-n

STATISTICS: mean, standard deviation, quartiles, regression

SOLVER: simultaneous linear, polynomial, non-linear, inequalities

FUNCTIONS: table of values (2 functions),

PROBABILITY: Normal, inverse Normal, Binomial, Poisson


POWER: Solar panel, battery backup

How to Use the FX-991EX

fx-991EX User Guide

Reference manual on how to operate every function on the fx-991EX calculator. Co…

Reference Leaflet
Poster fx-991EX

Full colour front view poster with Main Menu screen. A4, A3, A2, A1 and A0 size….

Reference Leaflet
fx-991EX Quick Start Guide

Overview of the menu functions of the fx-991EX with examples for the key apps. C…

How to Leaflet
fx-991EX Further Maths
Vector Quick Start fx-991EX

How to define dimensions and store vectors. Perform calculations such as subtrac…

How to Video
A-Level GCSE
Table of Values fx-991EX

How to create a table of values of a function with incremental steps. Extend th…

How to Leaflet
fx-991EX A-Level GCSE
Statistics Quick Start fx-991EX

How to calculate single variable and bivariate statistics such as mean, standard…

How to Leaflet
Spreadsheet Quick Start fx-991EX

How to enter data in a spreadsheet. Grab cell values and copy and paste formulae…

Reference Leaflet
Poster – Line Drawing fx-991EX

Full colour front view line drawing poster. A4, A3, A2, A1 and A0 size….

How to Video
Memory Functions fx-991EX

How to store results and calculated values. Perform operations with recalled val…

How to Leaflet
fx-991EX Further Maths
Matrix Quick Start fx-991EX

How to define and enter a matrix. Perform calculations and find the determinant….

fx-991EX A-Level Further Maths GCSE
Learning Mathematics fx-991EX

This teaching manual has a series of modules covering core mathematical skills b…

Reference Leaflet
Function Keys Quick Start fx-991EX

An overview of the functions available on the fx-991EX and the individual featur…

How to Leaflet
fx-991EX A-Level GCSE
Equation Quick Start fx-991EX

How to solve simultaneous equations with up to 4 unknowns. Solve polynomial equa…

How to Leaflet
fx-991EX A-Level
Distribution Quick Start fx-991EX

How to calculate probabilities for binomial, normal and poisson distributions. C…

How to Video
A-Level GCSE
Absolute Values fx-991EX

How to use the absolute or modulus function to create a table of values for a fu…

View More Resources

Classroom Emulator

Teachers can request a free licence for use in classrooms, remote and blended learning (available in the UK, Channel Islands, Isle of Man and Ireland). 

The free licence lasts for 1 year for demonstrating the calculator and preparing activities and is an ideal tool to embed mathematical understanding


Casio offer a large suite of resources available for UK schools and cover teaching with calculators alongside the most popular subject topics for GCSE and A Level.


The fx-85GTX is permitted in all UK, Irish and IB Diploma exams.


How can we help? Visit our FAQ page to find out more about our calculators.

Looking To Stock The Classroom?

Casio Education offer special school pricing on our scientific and graphic calculators.