Arb has been merged into FLINT -- use https://github.com/flintlib/flint/ instead

Small portable multiple-precision unsigned integer arithmetic in C

C-style arbitrary precision calculator

Arbitrary precision integer and rational arithmetic library

arbitrary precision arithmetic library

Arpra is a C library for analyzing the propagation of numerical error in arbitrary precision IEEE-754 floating-point computations.

Analytic Number Theory high-precision GnuMP routines

mirror of Fabrice Bellard's libbf tar releases

CASCADE is the C-library for Approximative Solutions to Complex Arbitrary Precision Differential Equations

C library for arbitrary-precision arithmetic

C library for arbitrary-precision integer and rational computation.

Proof of concept project about adding arbitrary precision math to Fractal generation software GNofract4D.

Simple, naive implementation of arbitrary precision floating point numbers. Example for finding Euler's number is provided.

A library for calculating with big numbers written in plain C. (GiantNbr's small brother)

Safe bindings to the GNU GMP library

A tiny Big Integer implementation in C for operations beyond 64 bits.

GNU bc using GMP

Calculate pi to arbitrary precision with GMP library, various formulas

LGMP-compatible Lua C API binding for GNU MPFR

Arbitrary-precision arithmetic, also called big-num arithmetic, multiple precision arithmetic, or sometimes infinite-precision arithmetic, indicates that calculations are performed on numbers whose digits of precision are limited only by the available memory of the host system.