mt_rand Generate a better random value &reftitle.description; intmt_rand intmt_rand intmin intmax 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 mt_getrandmax. If you want a random number between 5 and 15 (inclusive), for example, use mt_rand(5, 15). &reftitle.parameters; min Optional lowest value to be returned (default: 0) max Optional highest value to be returned (default: mt_getrandmax) &reftitle.returnvalues; A random integer value between min (or 0) and max (or mt_getrandmax, inclusive), or &false; if max is less than min. &reftitle.changelog; &Version; &Description; 5.3.4 Issues an E_WARNING and returns &false; if max < min. &changelog.randomseed; &reftitle.examples; ]]> &example.outputs.similar; &reftitle.notes; &caution.cryptographically-insecure; The distribution of mt_rand return values is biased towards even numbers on 64-bit builds of PHP when max is beyond 2^32. &reftitle.seealso; mt_srand mt_getrandmax openssl_random_pseudo_bytes rand