Qalculate!

Free and open-source calculator software From Wikipedia, the free encyclopedia

Qalculate! is an arbitrary precision cross-platform software calculator.^[8] It supports complex mathematical operations and concepts such as differentiation, integration, data plotting, and unit conversion. It is a free and open-source software released under GPL v2.

Original authorsHanna Knutsson, Sven Herzberg^[1]

DeveloperHanna Knutsson^[2]^[3]

Initial release2 August 2003; 22 years ago (version 0.1)^[4]^[5]^[6]

Stable release

5.2.0^[7]

/ 10 July 2024; 22 months ago

Quick facts Original authors, Developer ...

Qalculate!

A screenshot of qalculate-gtk
Original authors	Hanna Knutsson, Sven Herzberg^[1]
Developer	Hanna Knutsson^[2]^[3]
Initial release	2 August 2003; 22 years ago (2003-08-02) (version 0.1)^[4]^[5]^[6]

Stable release	5.2.0^[7] / 10 July 2024; 22 months ago (10 July 2024)

Written in	C++
Operating system	Linux Windows macOS
Platform	Winget Windows installer Snap Flatpak Standalone executable
Type	Math, calculator
License	GPL
Website	qalculate.github.io
Repository	github.com/Qalculate

Features

Qalculate! supports common mathematical functions and operations, multiple bases, autocompletion, complex numbers, infinite numbers, arrays and matrices, variables, mathematical and physical constants, user-defined functions, symbolic derivation and integration, solving of equations involving unknowns, uncertainty propagation using interval arithmetic, plotting using Gnuplot, unit and currency conversion and dimensional analysis, and provides a periodic table of elements, as well as several functions for computer science, such as character encoding and bitwise operations.^[9]^[10]^[11]^[12]^[13]^[14]^[15]^[16]^[17]

It provides four interfaces: two GUIs, one using GTK (qalculate-gtk) and another using Qt (qalculate-qt), a library for use in other programs (libqalculate), and a CLI program for use in a terminal (qalc).

Qalculate! (GTK+ GUI): qalculate-gtk^[18]
Qalculate! (Qt GUI): qalculate-qt
Qalculate! (CLI): qalc (usually provided by the libqalculate package)^[19]
Qalculate! (Library): libqalculate^[20]

Use in academic research

Bartel, Alexandre. "DOS Software Security: Is there Anyone Left to Patch a 25-year old Vulnerability?."
- "In our example of Figure 7, we choose to execute /usr/bin/qalculate-gtk, a calculator. Since the stack of the DOSBox process is non-executable, we cannot directly inject our shellcode on it."
- "The Gnome calculator was used to perform these calculations and the results were verified using the Qalculate! calculator and WolframAlpha (15) since spreadsheets are unable to perform these calculations."

References

[1]
"libqalculate ChangeLog". GitHub. 3 August 2025.
[2]
hanna-kn. "Overview". GitHub. Retrieved 28 April 2021.
[3]
Knutsson, Hanna. "Qalculate! Manual v5.7.0". qalculate.github.io. Retrieved 14 September 2025.
[4]
"Download Qalculate! From SourceForge.net". prdownloads.sourceforge.net. Archived from the original on 2 August 2003. Retrieved 13 January 2022.
[5]
"Qalculate! - A modern desktop calculator". SourceForge. Archived from the original on 2003-08-02. Retrieved 24 May 2021.
[6]
"Qalculate! - Browse Files at SourceForge.net". Archived from the original on 2004-05-21.
[7]
"Release 5.2.0". 1 July 2024. Retrieved 28 August 2024.
[8]
"downloads". Qalculate!. GitHub. Retrieved 28 April 2021.
[9]
"GUI Calculator for Linux". Ask Ubuntu. Retrieved 28 April 2021.
[10]
hanna-kn. "General problem with 'intelligent guessing' attempts · Issue #115". Qalculate/libqalculate. GitHub. Retrieved 28 April 2021. Also, qalculate-gtk (although I understand that you might prefer the CLI) allows you to see the parsed expression as you type and makes it easier to switch between modes. I agree that an alternative mode along the lines of your suggestions might be beneficial. The default mode should however still strive to allow the user to enter expressions as they appear in ordinary texts (it is still far from perfect in this respect), without the need to read a manual.
[11]
"Software used by the Math Center". Riverbend Community Math Center. South Bend, IN. Retrieved 28 April 2021. Qalculate! is a multi-purpose desktop calculator. It is small and simple to use but with much power and versatility underneath. Features include customizable functions, units, arbitrary precision, and plotting.
[12]
Liang Xu (2020-10-20). "Five commands to use calculator in Linux command line". fatalerrors.org. Archived from the original on 2021-04-28. Retrieved 28 April 2021. Qalculate is a multi-functional cross platform desktop calculator. It's easy to use, but it's powerful. It provides a number of powerful multi-functional mathematical libraries, as well as some practical tools to meet daily needs (such as currency conversion and percentage calculation, etc.). The functions of Qalculate include a large number of customizable function libraries, unit calculation and conversion, symbolic calculation (including integral and equation), arbitrary precision, uncertainty propagation, interval arithmetic, drawing and user-friendly interface (GTK + and CLI).
[13]
Shirish (July 18, 2020). "Qalculate! - The Best Calculator Application in The Entire Universe". It's FOSS. chmod777 Media Tech (OPC) Pvt Ltd. Retrieved 28 April 2021. Features include customizable functions, units, arbitrary precision, plotting, and a graphical interface that uses a one-line fault-tolerant expression entry (although it supports optional traditional buttons).
[14]
Oh, Damien (15 October 2010). "Qalculate is a Powerful Calculator For Linux". Make Tech Easier. Retrieved 28 April 2021. Qalculate is a powerful calculator for Linux that can solve complex mathematical expressions, units conversion, graph plotting and many more sophisticated functions.
[15]
Sharma, Shashank (8 October 2008). "In search of bigger, stronger calculators". Linux.com. Retrieved 28 April 2021. Qalculate!'s autocompletion feature quickly prompts you with all possible variables, functions, and units as soon as you start typing. For instance, on typing c, Qalculate! suggest circle, circumference, cal, cal-mean, candela, and more than a dozen more in-built values.
[16]
Devcic, Ivana Isadora (12 November 2015). "Make Math Easy with These Linux Apps". MUO - makeuseof.com. Retrieved 28 April 2021.
[17]
"Qalculate! Manual v3.21.0". qalculate.github.io. Retrieved 2021-10-30.
[18]
Berlasso, Ricardo. "2 scientific calculators for the Linux desktop". Opensource.com. Retrieved 28 April 2021. Qalculate! (with the exclamation point) has a long and complex history. The project offers a powerful library that can be used by other programs (the Plasma desktop can use it to perform calculations from krunner) and a graphical interface built on GTK3. It allows you to work with units, handle physical constants, create graphics, use complex numbers, matrices, and vectors, choose arbitrary precision, and more.
[19]
"QALC man page". qalculate.github.io.
[20]
Plasma desktop can use Library to perform calculations from krunner

Qalculate!

Features

Use in academic research

See also

References

External links

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