Casting And Power

<?php

$a = 2.5;
$b = 2.5;

print (int) $a * (int) $b;  // 4

print PHP_EOL;

print (int) $a ** (int) $b; // 6

?>

When you know that 2*2 = 4, and 2**2 = 4 (too), and 2.5 ** 2.5 = 9.8821176880262, you have to ask yourself where is this 6 coming from.

The answer is in the precedence. Casting has higher precedence than multiplication, so cast is done first (2.5 -> 2) then multiplication. This gives the first 4.

Then, power, **, as higher precedence than casting, so the second expression gives first 2.5 ** 2, which is 6.25, and then, cast it again as an integer, hence 6.

It’s a good thing that power is so little used.

See Also

• Cast And Power [Try me]

PHP Features

• cast

• exponent

• precedence

Last updated: 14 July 2026