- NAME
- SYNOPSIS
- DESCRIPTION
- RETURN VALUE
- SEE ALSO
- HISTORY

# NAME

RSA_size - get RSA modulus size

# SYNOPSIS

     #include <openssl/rsa.h>

     int RSA_size(const RSA *rsa);

# DESCRIPTION

This function returns the RSA modulus size in bytes. It can be used to determine how much memory must be allocated for an RSA encrypted value.

rsa->n must not be NULL.

# RETURN VALUE

The size in bytes.

# SEE ALSO

rsa

# HISTORY

`RSA_size()` is available in all versions of SSLeay and OpenSSL.