(PHP 4 >= 4.0.4, PHP 5, PHP 7)

gmp_randomRandom number


This function has been DEPRECATED as of PHP 7.2.0, and REMOVED as of PHP 8.0.0. Relying on this function is highly discouraged.


gmp_random(int $limiter = 20): GMP

Generate a random number. The number will be between 0 and (2 ** n) - 1, where n is the number of bits per limb multiplied by limiter. If limiter is negative, negative numbers are generated.

A limb is an internal GMP mechanism. The number of bits in a limb is not static, and can vary from system to system. Generally, the number of bits in a limb is either 32 or 64, but this is not guaranteed.


This function does not generate cryptographically secure values, and must not be used for cryptographic purposes, or purposes that require returned values to be unguessable.

If cryptographically secure randomness is required, the Random\Randomizer may be used with the Random\Engine\Secure engine. For simple use cases, the random_int() and random_bytes() functions provide a convenient and secure API that is backed by the operating system’s CSPRNG.



The limiter.

A GMP object, an int or a numeric string.

Return Values

A random GMP number.


Example #1 gmp_random() example

= gmp_random(1); // random number from 0 to 1 * bits per limb
$rand2 = gmp_random(2); // random number from 0 to 2 * bits per limb

echo gmp_strval($rand1) . "\n";
gmp_strval($rand2) . "\n";

The above example will output:


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User Contributed Notes 1 note

asphp at dsgml dot com
7 years ago
Warning: Do not use this function.

Use gmp_random_bits() or gmp_random_range() instead.

The documentation and the code for this function do NOT match, and in any case this function is quite useless.
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