microtime()

microtime() — Return current Unix timestamp with microseconds.

Built-in function of PHP 8.5. The manual lists it as available in PHP 4, PHP 5, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.

What it does

microtime() returns the current Unix timestamp with microseconds. This function is only available on operating systems that support the gettimeofday() system call.

Signature

microtime(bool $as_float = false): string|float

Parameters

Parameter	Type	What it takes
$as_float	bool	If used and set to true, microtime() will return a float instead of a string, as described in the return values section below.

Return value

By default, microtime() returns a string in the form "msec sec", where sec is the number of seconds since the Unix epoch (0:00:00 January 1,1970 GMT), and msec measures microseconds that have elapsed since sec and is also expressed in seconds as a decimal fraction. If as_float is set to true, then microtime() returns a float, which represents the current time in seconds since the Unix epoch accurate to the nearest microsecond.

Example

A runnable snippet:

$time_start = microtime(true); // Sleep for a while usleep(10_000); $time_end = microtime(true); $time = $time_end - $time_start; print "Did nothing in $time seconds\n";