Cairo Math 64×61

A fixed point 64.61 math library for Cairo & Starknet

Signed 64.61 Fixed Point Numbers

A signed 64.61-bit fixed point number is a fraction in which the numerator is a signed 125-bit integer and the denominator is 2^61. Since the denominator stays the same there is no need to store it (as in a floating point value).

64.61 is utilized as the 125 bit representation allows for overflow up to 2^125 * 2^125 (250 bits) during calculation taking advantage of Cairo’s 251 bit felts.

Can represent values in the range of -2^64 to 2^64 with precision to 4.34e-19.

Standard Library

Math64x61 includes implementation of mul, div, sqrt, exp, ln, log2, log10, and pow as well as conversion and assertion methods.

Trigonometry Library

Trig64x61 includes implementation of sin, cos, tan and their inverses.

Hyperbolic Library

Hyp64x61 includes implementation of sinh, cosh, tanh, and their inverses.


This library strives to adhere to the OpenZeppelin extensibility pattern:


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