GNOME Calculator, formerly known as gcalctool, is the software calculator integrated with the GNOME desktop environment.

It is programmed in C and Vala and part of the GNOME Core Applications.

The GNOME calculator uses the common infix notation for binary functions, such as the four basic arithmetic operations.

Unlike many other calculators, it uses prefix notation, not postfix notation for unary functions.

The decimal separator on the number pad is based on the general keyboard layout since version 3.12.3.