This article is about the electronic device. For mechanical precursors to the modern calculator, see Mechanical calculator. For other uses, see Calculator (disambiguation).
An electronic pocket calculator with a liquid-crystal display (LCD) seven-segment display, that can perform arithmetic operations.
A modern scientific calculator with a dot matrix LCD.

An electronic calculator is a small, portable electronic device used to perform operations ranging from basic arithmetic to complex mathematics.

The first solid state electronic calculator was created in the 1960s, building on the extensive history of tools such as the abacus (developed around 2000 BC), and the mechanical calculator (developed in the 17th century AD). It was developed in parallel with the analog computers of the day.

The pocket sized devices became available in the 1970s, especially after the first microprocessor, the Intel 4004, developed by Intel for the Japanese calculator company Busicom. They later became used commonly within the petroleum industry (oil and gas).

Modern electronic calculators vary: from cheap, give-away, credit-card-sized models to sturdy desktop models with built-in printers. They became popular in the mid-1970s (as integrated circuits made their size and cost small). By the end of that decade, calculator prices had reduced to a point where a basic calculator was affordable to most and they became common in schools.

Computer operating systems as far back as early Unix have included interactive calculator programs such as dc and hoc, and calculator functions are included in almost all personal digital assistant (PDA) type devices (save a few dedicated address book and dictionary devices).

In addition to general purpose calculators, there are those designed for specific markets. For example, there are scientific calculators which include trigonometric and statistical calculations. Some calculators even have the ability to do computer algebra. Graphing calculators can be used to graph functions defined on the real line, or higher-dimensional Euclidean space. As of 2016, basic calculators cost little, but the scientific and graphing models tend to cost more.

In 1986, calculators still represented an estimated 41% of the world's general-purpose hardware capacity to compute information. By 2007, this diminished to less than 0.05%. [1]


Scientific calculator displays of fractions and decimal equivalents.


Modern 2016 electronic calculators contain a keyboard with buttons for digits and arithmetical operations; some even contain "00" and "000" buttons to make larger or smaller numbers easier to enter. Most basic calculators assign only one digit or operation on each button; however, in more specific calculators, a button can perform multi-function working with key combinations.

Display output

Calculators usually have liquid-crystal displays (LCD) as output in place of historical light-emitting diode (LED) displays and vacuum fluorescent displays (VFD); details are provided in the section Technical improvements.

Large-sized figures and comma separators are often used to improve readability. Various symbols for function commands may also be shown on the display. Fractions such as 13 are displayed as decimal approximations, for example rounded to 0.33333333. Also, some fractions (such as 17, which is 0.14285714285714; to 14 significant figures) can be difficult to recognize in decimal form; as a result, many scientific calculators are able to work in vulgar fractions or mixed numbers.


Calculators also have the ability to store numbers into computer memory. Basic types of these store only one number at a time; more specific types are able to store many numbers represented in variables. The variables can also be used for constructing formulas. Some models have the ability to extend memory capacity to store more numbers; the extended memory address is termed an array index.

Power source

Power sources of calculators are: batteries, solar cells or mains electricity (for old models), turning on with a switch or button. Some models even have no turn-off button but they provide some way to put off (for example, leaving no operation for a moment, covering solar cell exposure, or closing their lid). Crank-powered calculators were also common in the early computer era.

Key layout

Usual basic pocket calculator layout
C ±  %
7 8 9 ÷
4 5 6 ×
1 2 3
0 . = +
MC or CM Memory Clear
MR or RM Memory Recall
M- Memory Subtraction
M+ Memory Addition
C or AC All Clear
CE Clear (last) Entry; sometimes called CE/C: a first press clears the last entry (CE), a second press clears all (C)
± Toggle positive/negative number
 % Percent
÷ Division
× Multiplication
+ Addition
. Decimal point
Square root
= Result