API Reference    



- the ultimate desktop calculator

Qalculate! is a multi-purpose cross-platform desktop calculator. It is simple to use but provides power and versatility normally reserved for complicated math packages, as well as useful tools for everyday needs (such as currency conversion and percent calculation). Features include a large library of customizable functions, unit calculations and conversion, physical constants, symbolic calculations (including integrals and equations), arbitrary precision, uncertainty propagation, interval arithmetic, plotting, and a user-friendly interface (GTK+ and CLI).

Qalculate! is free software, licensed under the GNU Public License v2 (or later).

This project welcomes new developers. Visit the project page here.


Latest News

.: 2020-06-26 :. Qalculate! is now avilable at Flathub

The flatpak package (for Linux) has now finally been added to Flathub ( To install the package follow the link or use the command "flatpak install".

Flatpak users are adviced to replace previous installations. Note however that the app-id has changed. In order to preserve configuration and data you will have to manually copy the files (from ~/.var/app/io.github.qalculate.Qalculate to ~/.var/app/io.github.Qalculate).

For Windows users, Qalculate! was recently added to the Windows Package Manager (winget) community repository, making updates easier.

.: 2020-06-22 :. Qalculate! version 3.11 released

List of changes:
  • Allow multiple "to"-conversions in one expression (e.g. "5 m/s to hex to ft to h = 0xE6AF.1E*ft∕h)
  • Support specification of number of bits for hexadecimal "to" conversion (4 to hex16 = 0004)
  • Improvements and fixes for sexagesimal numbers and time format
  • Support for +, -, (, ) Unicode superscripts, and N-Ary Summation symbol
  • Syntax highlighting using colours in qalc
  • Enable Unicode by default in qalc (on platforms other than Windows)
  • Improved display of unit expressions
  • Option to clear history on exit (GUI)
  • Fix removal of history items, and move to top, when calculate-as-you-type is activated (GUI)
  • Reduce the height of the result widget (GUI)
  • Hide tooltip after keypad button click (GUI)
  • Check for updates menu item (GUI)
  • Slovenian translation (GUI)
  • Support for automatic updates of self-contained binaries
  • Fix segfault when parsing an expression that contains a prefix with more than one letter followed by a unit and an exponent without exponentiation operator
  • Fix use of equals sign in qalc command line arguments (e.g. "qalc --base=16")
  • Fixes for the Gnome shell search provider
  • Minor bug fixes and feature improvements
Get the new version from the downloads page.