Frink - A practical calculating tool, unit conversion utility, and programming language designed to make physical calculations simple.

galculator - galculator is an open source scientific calculator with a modern GUI and a wide range of operation modes. It supports algebraic, reverse polish (RPN) and paper mode notations.

NimbleText - NimbleText is a text manipulation and code generation tool available online or as a free download.

SpeedCrunch - SpeedCrunch. SpeedCrunch is a high-precision scientific calculator featuring a fast, keyboard-driven user interface. It is free and open-source software, licensed under the GPL. Download Documentation Donate .

Event Viewer - Get help, support, and tutorials for Windows products—Windows 10, Windows 8.1, Windows 7, and Windows 10 Mobile.

Desmos - A beautiful, innovative, and modern online graphing calculator.