Which is faster in PHP, $array[] = $value or array_push($array, $value)?

What's better to use in PHP for appending an array member,

$array[] = $value;

or

array_push($array, $value);

?

Though the manual says you're better off to avoid a function call, I've also read $array[] is much slower than array_push(). What are some clarifications or benchmarks?

I personally feel like $array[] is cleaner to look at, and honestly splitting hairs over milliseconds is pretty irrelevant unless you plan on appending hundreds of thousands of strings to your array.

I ran this code:

$t = microtime(true);
$array = array();
for($i = 0; $i < 10000; $i++) {
    $array[] = $i;
}
print microtime(true) - $t;
print '<br>';
$t = microtime(true);
$array = array();
for($i = 0; $i < 10000; $i++) {
    array_push($array, $i);
}
print microtime(true) - $t;

The first method using $array[] is almost 50% faster than the second one.

Some benchmark results:

Run 1
0.0054171085357666 // array_push
0.0028800964355469 // array[]

Run 2
0.0054559707641602 // array_push
0.002892017364502 // array[]

Run 3
0.0055501461029053 // array_push
0.0028610229492188 // array[]

This shouldn't be surprising, as the PHP manual notes this:

> If you use array_push() to add one element to the array it's better to use $array[] = because in that way there is no overhead of calling a function.

The way it is phrased I wouldn't be surprised if array_push is more efficient when adding multiple values. Out of curiosity, I did some further testing, and even for a large amount of additions, individual $array[] calls are faster than one big array_push. Interesting.

The main use of array_push() is that you can push multiple values onto the end of the array.

It says in the documentation:

> If you use array_push() to add one > element to the array it's better to > use $array[] = because in that way > there is no overhead of calling a > function.

From the PHP documentation for array_push:

> Note: If you use array_push() to add one element to the array it's better to use $array[] = because in that way there is no overhead of calling a function.

Word on the street is that [] is faster because no overhead for the function call. Plus, no one really likes PHP's array functions...

"Is it...haystack, needle....or is it needle haystack...ah, f*** it...[] = "

One difference is that you can call array_push() with more than two parameters, i.e. you can push more than one element at a time to an array.

$myArray = array();
array_push($myArray, 1,2,3,4);
echo join(',', $myArray);

prints 1,2,3,4

A simple $myarray[] declaration will be quicker as you are just pushing an item onto the stack of items due to the lack of overhead that a function would bring.

Since "array_push" is a function and it called multiple times when it is inside the loop, it will allocate memory into the stack.

But when we are using $array[] = $value then we are just assigning a value to the array.

Second one is a function call so generally it should be slower than using core array-access features. But I think even one database query within your script will outweight 1000000 calls to array_push().

See here for a quick benchmark using 1000000 inserts: https://3v4l.org/sekeV

I just wan't to add : int array_push(...) returns the new number of elements in the array (PHP documentation). which can be useful and more compact than $myArray[] = ...; $total = count($myArray);.

Also array_push(...) is meaningful when variable is used as a stack.