SMath Studio - Tiny, powerful, free mathematical program with WYSIWYG editor and complete units of measurements support.
Numi App - Numi is a beautiful text calculator for Mac.
Wolfram Mathematica - Mathematica has characterized the cutting edge in specialized processing—and gave the chief calculation environment to a large number of pioneers, instructors, understudies, and others around the globe.
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 .
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming
Qalculate! - Qalculate! is a multiplatform multi-purpose desktop calculator.