Skip to Content


Allows the ability to time tasks in PHP.

PHP December 18, 2018


nebula()->timer($unique_id, $action, $category)


(Required) (String) A unique ID for this specific timed task
Default: None

(Optional) (String) A start/mark/stop action
Default: "start"

(Optional) (String) Group timings together to be added together
Default: false

Parameter Notes

Actions currently include “start”, “mark” (with an alias of “once”), and “end” (with an alias of “stop”).

Although the $unique_id is required, if the ID is not unique a random number will be appended to it that begins with _d

On start actions, the used unique ID is returned so that the timer can be stopped later.

Request or provide clarification »


Time a single task

nebula()->timer('Example Task');
// something here
nebula()->timer('Example Task', 'end');

Time a task that may be called more than once

$task_name = nebula()->timer('Possible Multiple Tasks');
// something here
nebula()->timer($task_name, 'end');

Categories multiple similar tasks

foreach ( $big_list as $item ){
  nebula()->timer('Big List Task (' . $item . ')', 'start', 'Big List');
  // something here
  nebula()->timer('Big List Task (' . $item . ')', 'end');

Combine timings from a single category

if ( !empty($this->server_timings['categories']) && !empty($this->server_timings['categories']['Big List']) ){
    foreach ( $this->server_timings['categories']['Big List'] as $category => $times ){
        $big_list_total = array_sum($times);

Mark a point in time with a single entry that immediately starts and stops.

nebula()->timer('Certain Point in Time', 'mark');



Open the JavaScript console to see the data for this example.

Start Timer

New Lap


Additional Notes

Timings are stored in nebula()->server_timings and categories are separated into a nebula()->server_timings['categories'] array.

Timings will automatically appear for developers, but the query string ?timings must be used for non-developers (or logged-out users).

Server Timing API

Timings are sent via the server-timing HTTP header and can be viewed in Chrome DevTools under Network by clicking the page resource and choosing the Timing tab. It is important to note that these times are finalized before headers are sent.

This timing header is also available in other speed testing tools (like that provide access to response headers.

JavaScript Console Table

Timings are also available in the JavaScript console within the Performance group. Expand it to see all server timings as well as client-side timings as well in a sortable table. Timings are finalized again at the last possible moment to make sure they are complete.

Timings are available in the WordPress admin area too.

Source File

Located in /libs/Utilities/Utilities.php on line 1068.

No Hooks

This function does not have any filters or actions available. Request one?
        public function timer($unique_id, $action='start', $category=false){
            //Unique ID is required
            if ( empty($unique_id) || in_array(strtolower($unique_id), array('start', 'stop', 'end')) ){
                return false;

            if ( $action === 'start' || $action === 'mark' || $action === 'once' ){
                //Prevent duplicates by appending a random number to the ID (only when duplicate)
                if ( !empty($this->server_timings[$unique_id]) ){
                    $unique_id .= '_d' . rand(10000, 99999);

                $this->server_timings[$unique_id] = array(
                    'start' => microtime(true),
                    'active' => true,
                    'category' => $category

                //Immediately stop one-off timing marks
                if ( $action === 'mark' || $action === 'once' ){
                    $this->server_timings[$unique_id]['end'] = $this->server_timings[$unique_id]['start']+0.001;
                    $this->server_timings[$unique_id]['time'] = 0.001; //Force non-empty time of 1 millisecond
                    $this->server_timings[$unique_id]['active'] = false;

                    //Add to array of this category (if categorization is used)
                    if ( !empty($category) ){
                        $this->server_timings['categories'][$category][] = 0.001; //Force non-empty time of 1 millisecond

                return $unique_id; //Return the unique ID in case it was changed so that the 'end' call can know what to use
            } elseif ( in_array(strtolower($action), array('stop', 'end')) ){
                if ( !empty($this->server_timings[$unique_id]['start']) ){ //Make sure this timer has started
                    $this->server_timings[$unique_id]['end'] = microtime(true);
                    $this->server_timings[$unique_id]['time'] = $this->server_timings[$unique_id]['end'] - $this->server_timings[$unique_id]['start'];
                    $this->server_timings[$unique_id]['active'] = false;

                    //Add to array of this category (if categorization is used)
                    $this_category = $this->server_timings[$unique_id]['category'];
                    if ( !empty($this_category) ){
                        $this->server_timings['categories'][$this_category][] = $this->server_timings[$unique_id]['time'];

                    return true;

            return false;


This function can not be short-circuited with an override filter. Request one?