Operators

Arithmetic operators

Operator Name Result
-$a negation Opposite of $a.
$a + $b addition Sum of $a and $b.
$a - $b Subtraction Difference of $a and $b.
$a * $b Multiplication Product of $a and $b.
$a / $b division Quotient of $a and $b.
$a % $b modulus Remainder of $a divided by $b.
$a ** $b Exponentiation Result of raising $a to the $b’th power.

Comparison operators

Operator Name Result
$a == $b Equal TRUE if $a is equal to $b after type juggling.
$a === $b Identical TRUE if $a is equal to $b, and they are of the same type.
$a != $b Not equal TRUE if $a is not equal to $b after type juggling.
$a <> $b Not equal TRUE if $a is not equal to $b after type juggling.
$a !== $b Not identical TRUE if $a is not equal to $b, or they are not of the same type.
$a < $b Less than TRUE if $a is strictly less than $b.
$a > $b Greater than TRUE if $a is strictly greater than $b.
$a <= $b Less than or equal to TRUE if $a is less than or equal to $b.
$a >= $b Greater than or equal to TRUE if $a is greater than or equal to $b.
$a <=> $b Spaceship -1 if $a is less than $b, 1 if $a is greater than $b, otherwise 0.

Logical operators

Operator Name Result
! $a Not TRUE if $a is not TRUE.
$a && $b And TRUE if both $a and $b are TRUE.
$a || $b Or TRUE if either $a or $b is TRUE.
$a and $b And Like && but precedence is lower.
$a or $b Or Like || but precedence is lower.
$a xor $b Xor TRUE if either $a or $b is TRUE, but not both.

Simple-assignment operators

The simple-assignment operator = assigns its right operand to its left operand.

<?php
$a = 1;
echo $a; // 1

Compound-assignment operators

The compound-assignment operators combine the simple-assignment operator with another binary operator. Compound-assignment operators perform the operation specified by the additional operator, then assign the result to the left operand.

Operator Shorthand Meaning
+= $x += $y $x = $x + $y
-= $x += $y $x = $x - $y
*= $x += $y $x = $x * $y
/= $x += $y $x = $x / $y
%= $x %= $y $x = $x % $y
**= $x += $y $x = $x ** $y
.= $x .= $y $x = $x . $y
<<= $x <<= $y $x = $x << $y
>>= $x >>= $y $x = $x >> $y
&= $x &= $y $x = $x & $y
^= $x ^= $y $x = $x ^ $y
|= $x |= $y $x = $x | $y