A scientific calculator that supports math-like syntax with user-defined variables, functions, derivation, integration, and complex numbers.

GitHub Repo
>> f(x) = x(3x + 1) ← Declare functions >> a₁ = 1÷6 ← Declare variables >> 6ia√(f'(a₁))← Derivation 1.4142135624i 2i ← Complex numbers >> (0, π, sin2ix, dx) + e^(πi) ÷ 3 ← Integration -0.3333333333 + 133.3733807458i ≈ -1/3 + 133.3733807458i >> Σ(0, 720, 1÷n!) ← Calculating sums 2.7182818285 e
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All the calculator features and how they're used.


Completion for special symbols

You can type special symbols (such as √) by typing the normal function or constant name and pressing tab.


Variables are defined with the following syntax: name = value

Examples: x = 3/4


Functions are defined with the following syntax: name(param1, param2, etc.) = value

Examples: f(x) = 2x+3 A(x, y) = (xy)/2

They are used like this: name(arg1, arg2, etc.)

Examples: f(3) + 3 A(2, 3)

Derivation can be done like this: name'(arg1)

Examples: f'(3) + 3 sin'(pi)

Predefined functions



Kalker looks for kalker files in the system config directory. If a file with the name default.kalker is found, it will be loaded automatically every time kalker starts. Any other files in this directory with the .kalker extension can be loaded at any time by doing load filename in kalker. Note that the extension should not be included here.


kalker officially runs on Linux, Windows, macOS, and Android.

Download for Android