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# mt_rand

(PHP 3>= 3.0.6, PHP 4 , PHP 5)

mt_rand -- Generate a better random value

## Description

int mt_rand ( [int min, int max])

Many random number generators of older libcs have dubious or unknown characteristics and are slow. By default, PHP uses the libc random number generator with the rand() function. The mt_rand() function is a drop-in replacement for this. It uses a random number generator with known characteristics using the Mersenne Twister, which will produce random numbers four times faster than what the average libc rand() provides.

If called without the optional `min`, `max` arguments mt_rand() returns a pseudo-random value between 0 and `RAND_MAX`. If you want a random number between 5 and 15 (inclusive), for example, use `mt_rand (5, 15)`.

Example 1. mt_rand() example
`<?php echo mt_rand() . "\n"; echo mt_rand() . "\n"; echo mt_rand(5, 15); ?>`
The above example will output something similar to:
    1604716014
    1478613278
    6

> Note: As of PHP 4.2.0, there is no need to seed the random number generator with srand() or mt_srand() as this is now done automatically.

> Note: In versions before 3.0.7 the meaning of `max` was `range`. To get the same results in these versions the short example should be `mt_rand (5, 11)` to get a random number between 5 and 15.

See also: mt_srand(), mt_getrandmax(), and rand().

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