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

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

MyScript Calculator

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

Free Android iPhone Android Tablet iPad

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

Real-Time Currency Converter

CURRENCY EXCHANGE CONVERTER App will help you to find the value of any country's currency and compare it to the currencies of other countries with on click ,it...

Free Android

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

Elk

Elk is a super fast way to convert currencies, interacting with set values across increments accessed using simple swipes. No need to enter values with a keypad, it lets...

Free iPhone

Free Currency Converter

Currency exchange rate calculator and exchange rates list for your android device – Free Edition from Viftech Solutions. Download “Currency Converter” right now to get...

Free Android

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

errProof

The website has a lot of useful and unique tools.

Free Web

Unit Wolf

Unit Wolf is a unit conversion program created for quick and reliable conversions. Enter entire equations or just simple numbers. Convert between 170 currencies or...

Free Web

Convertr

Convertr, a unit and currency conversion app. Elegant, surprisingly minimalist and amazingly fast, Convertr offers innovative scroll and zoom feature that provides...

Freemium Android iPhone Android Tablet iPad

gUnit

gUnit covers every possible conversion need you may encounter. You can figure out how much a meal might cost you in US Dollars while you're traveling in Switzerland...

Freemium iPhone

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

A to Z Converter

"A to Z Converter" provides a set of free converters to easily convert between anything to anything else. Be it Units, Colors, Age, Timezone or Currency. Now...

Free Android