Wolfram Alpha

Wolfram Alpha is a "Computational Knowledge Engine" - different from a search engine, it answers factual queries directly by computing the answer from structured data, rather than providing a list of documents or web pages that...

Freemium Android iPhone iPad Web Kindle Fire Windows Phone

Gnome calculator

Calculator for the GNOME Desktop Environment, formerly known as gcalc (and gcalctool CLI).

Free Open Source Linux GNOME

NaSC

Its an app where you do maths like a normal person. It lets you type whatever you want and smartly figures out what is math and spits out an answer on the right pane.

Free Open Source Linux

Excalibur

Excalibur for Windows 32-bit version is a freeware full featured RPN-only calculator. This is a serious calculator for serious users. Excalibur takes up a small amount of resources for all it does so well.

Free Windows

Calculator++

A multipurpose calculator app with slick and intuitive user interface. Access additional features from the main screen of the app using gestures. It has a big variety of built-in functions and supports adding new user-defined functions.

Free Open Source Android Android Tablet

Giac/Xcas

Giac/Xcas is a free computer algebra system for Windows, Mac OS X and Linux/Unix (license GPL3, for commercial dual-license contact us).

Free Open Source Mac OS X Windows Linux

Precise Calculator

Programmable scientific calculator which has more than 150 mathematical functions and all of them return as many digits as you need. It can calculate with real numbers, complex numbers, fractions, vectors, matrices.

Free Open Source Windows

Arithmate Pro Calculator

A modern, scientific calculator that is easy to use. While other calculators display only one number at a time, this one shows you the whole expression you are inputting, leading to a much more user friendly experience.

Commercial Android

Omni Calculator

Omni Calculator is a web/mobile calculator that solves concrete problems such as mortgage payment, gross margin, body mass index, break-even point, etc.

Free Android iPhone iPad Web

ESBCalc

ESBCalc is a Freeware Scientific Calculator for Windows with Infix Notation, Brackets, Scientific Functions (Trigonometric, Hyperbolic, Logarithmic - including Base 10, Base 2 & Natural - plus more), Memory, Paper Trail, Result History...

Freemium Windows

MyScript Calculator

With MyScript Calculator, perform mathematical operations naturally using your handwriting.

Free Android iPhone Android Tablet iPad

Insect

High precision scientific calculator with full support for physical units (web and terminal versions).

Free Open Source Mac OS X Windows Linux Web Self-Hosted

XCALC

XCALC is my little RPN calculator completely free to use, and still downloadable. XCALC is now a DEAD project. No work has been done on this project since 2012, and nothing more will be done either.

Free Open Source Windows Linux

Calculator Plus

Calculator Plus is a nice addition to hundreds of Calculator apps but with unique idea and innovative and user friendly designed buttons. A sound and smart person...

Free Android

eCalc Scientific Calculator

An easy to use scientific calculator with many advanced features to help you solve algebra, trigonometry, and engineering math problems. The calculator comes with six...

Commercial Mac OS X Windows

Calculate

A math expression calculator with persistent memory for variables and functions. Any JavaScript expression can be evaluated. - Click the C button to clear the output...

Free Mac OS X

CCCalc

CCCalc is a calculator with tape, you can correct any printed character with, and the tape recalculates everything itself. Unlimited precision, visible and even...

Free Windows

Online Terminal Calculator

Online terminal based calculator, it is one of the most productive calculator in online, it uses terminal based approach instead of traditional push button based.

Free Web

errProof

The website has a lot of useful and unique tools.

Free Web