(PHP 4, PHP 5, PHP 7)
rand — Generate a random integer
rand ( ) : int
rand ( int $min , int $max ) : int
If called without the optional min
, max
arguments rand() returns a pseudo-random integer between 0 and getrandmax(). If you want a random number between 5 and 15 (inclusive), for example, use rand(5,
15)
.
This function does not generate cryptographically secure values, and should not be used for cryptographic purposes. If you need a cryptographically secure value, consider using random_int(), random_bytes(), or openssl_random_pseudo_bytes() instead.
Note: On some platforms (such as Windows), getrandmax() is only 32767. If you require a range larger than 32767, specifying
min
andmax
will allow you to create a range larger than this, or consider using mt_rand() instead.
Note: As of PHP 7.1.0, rand() uses the same random number generator as mt_rand(). To preserve backwards compatibility rand() allows
max
to be smaller thanmin
as opposed to returningfalse
as mt_rand().
min
The lowest value to return (default: 0)
max
The highest value to return (default: getrandmax())
A pseudo random value between min
(or 0) and max
(or getrandmax(), inclusive).
Version | Description |
---|---|
7.2.0 | rand() has received a bug fix for a modulo bias bug. This means that sequences generated with a specific seed may differ from PHP 7.1 on 64-bit machines. |
7.1.0 | rand() has been made an alias of mt_rand(). |
Example #1 rand() example
<?php echo rand() . "\n"; echo rand() . "\n"; echo rand(5, 15); ?>
The above example will output something similar to:
7771 22264 11
min
max
range must be within the range getrandmax(). i.e. (max
- min
) <= getrandmax() Otherwise, rand() may return poor-quality random numbers.
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.rand.php