DonateQalculate!
- 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, Qt, and CLI).
Qalculate! is free software, licensed under the GNU Public License v2 (or later).
Latest News
2025-10-13
Qalculate! version 5.8 released
Changes:
- Add output in scientific (sci), engineering (eng), ans simple notation as "to"-operator options
- Improve support (and fix segfault) for exponential notation in hexadecimal numbers
- Add TeX point, TeX scaled point, twip, agate, darcy, kayser, lambert, foot-lambert, and cc units
- Add compton wavelength constants for muon, neutron, proton, and tau
- Update calculation of fraction of year (with day counting basis 0 and 1) to match method used in spreadsheets other than Gnumeric
- Change default quantile algorithm from 8 to 7
- Improve accuracy for intervals in solutions to equations when using interval arithmetic
- Fix poolvar(), ttest(), cor(), dollarde() and dollarfr() functions
- Fix inequality with 1/f(x) on one side, e.g. "1/(x-2) ≤ 2"
- Fix segfault with extremely small numbers and high number of bits in floating point conversion
- Fix crashes and freezes in some corner cases
- Fix value of Planck unit (was rounded to 7 decimals)
- Show warning about default assumptions the first time an equation is solved
- Show warning symbol when calculate as you type expression results in a question
- Show warning and ask for confirmation when deactivating interval arithmetic
- Improve completion
- Add "save config" option (if disabled qalc.cfg is never automatically updated) and relocate qalc.history to $XDG_STATE_HOME (CLI)
- Increase speed when calculating many expressions from file (CLI)
- Fix support for prompt string containing Unicode characters, control characters, and/or escape sequences (CLI)
- Automatically recalculate expression with current time every second (CLI, Qt)
- Replace edit-clear icon on keypad button with "C" (Gtk, Qt)
- Support non-existing X-variables in plot dialog (Gtk, Qt)
- Fix floating point value in floating point conversion dialog for extended and microchip formats (Gtk, Qt)
- Automatically calculate expression selection if calculate as you type is enabled (Gtk)
- Enable calculate as you type by default (Gtk)
- Add option to add or edit comment in history (Gtk)
- Add option to clear expression or replace with result after calculation (Gtk)
- Fix custom time zone in calculate as you type result when added to history (Gtk)
- Improve automatic digit grouping (Qt)
- Add option to place percent/remainder button in number pad (Qt)
- Add asterisk and middle dot as multiplication sign alternatives in preferences (Qt)
- Add options to show a status bar and to place expression field below history (Qt)
- Fix updating of fields in plot dialog when expression list selection changes (Qt)
- Fixes for comments and removal of single result (Qt)
- Fix initial state of "Use E-notation instead of 10^n" in preferences (Qt)
- Many minor bug fixes and feature enhancements