---
name: "frexp"
section: "3"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["linux", "freebsd"]
url: "https://new.carta.tech/frexp"
---

# frexp(3)

convert floating-point number to fractional and integral components

## NAME

**frexp**, **frexpf**, **frexpl** – convert floating-point number to fractional and integral components

## LIBRARY

Math Library (libm, -lm)

## SYNOPSIS

**#include \<math.h\>**

*double*\

**frexp**(*double value*, *int \*exp*);

*float*\

**frexpf**(*float value*, *int \*exp*);

*long* *double*\

**frexpl**(*long double value*, *int \*exp*);

## DESCRIPTION

The **frexp**(), **frexpf**() and **frexpl**() functions break a floating-point number into a normalized fraction and an integral power of 2. They store the integer in the *int* object pointed to by *exp*.

## RETURN VALUES

These functions return the value *x*, such that *x* is a *double* with magnitude in the interval \[1/2, 1) or zero, and *value* equals *x* times 2 raised to the power *\*exp*. If *value* is zero, both parts of the result are zero.

## SEE ALSO

[ldexp(3)](/ldexp/3.md), [math(3)](/math/3.md), [modf(3)](/modf/3.md)

## STANDARDS

The **frexp**(), **frexpf**(), and **frexpl**() functions conform to ISO/IEC 9899:1999 (“ISO C99”).