get_the_post_thumbnail_url( int|WP_Post|null $post = null, string|int[] $size = 'post-thumbnail' ): string|false
- Since
- 4.4.0
- Source
wp-includes/post-thumbnail-template.php:250
Compatibility
- WordPress
- since 4.4.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$postint|WP_Post|nulloptional- Post ID or WP_Post object. Default is global
$post.Default:null $sizestring|int[]optional- Registered image size to retrieve the source for or a flat array of height and width dimensions. Default 'post-thumbnail'.Default:
'post-thumbnail'
Return value
string|false- Post thumbnail URL or false if no image is available. If
$sizedoes not match any registered image size, the original image URL will be returned.
Performance profile
How much work a call to get_the_post_thumbnail_url() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Heavy
- Scaling
- Constant
- Instructions
- 8–19
- Plugin surface
- 1 hook
- Called by
- 3
Reaches the database via get_post().
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 20.
Third-party callbacks on 'post_thumbnail_url' run inside this call, and their cost is not bounded by anything here.
3 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
apply_filters()called directly - querycontent query
get_post()one call below get_the_post_thumbnail_url()
Further down the call graph this can also reach cache, serialize, option and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost get_the_post_thumbnail_url() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 8 | get_post_thumbnail_id() |
| always | 19 | get_post_thumbnail_id(), wp_get_attachment_image_url(), apply_filters() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 20 instructions, 8–19 executed per call, 1 branch. The work does not change between versions.
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Hooks and filters fired · 1
One hook fires while get_the_post_thumbnail_url() runs, in this order:
- apply_filters( post_thumbnail_url )filterline 269 (+19 into the body)
Filters the post thumbnail URL.
Uses · 3
- get_post_thumbnail_id()Retrieves the post thumbnail ID.
- wp_get_attachment_image_url()Gets the URL of an image attachment.
- apply_filters()Calls the callback functions that have been added to a filter hook.
Used by · 3
- render_block_core_cover()Renders the `core/cover` block on server.
- render_block_core_media_text()Renders the `core/media-text` block on server.
- the_post_thumbnail_url()Displays the post thumbnail URL.
Source code
function get_the_post_thumbnail_url( $post = null, $size = 'post-thumbnail' ) { $post_thumbnail_id = get_post_thumbnail_id( $post ); if ( ! $post_thumbnail_id ) { return false; } $thumbnail_url = wp_get_attachment_image_url( $post_thumbnail_id, $size ); /** * Filters the post thumbnail URL. * * @since 5.9.0 * * @param string|false $thumbnail_url Post thumbnail URL or false if the post does not exist. * @param int|WP_Post|null $post Post ID or WP_Post object. Default is global `$post`. * @param string|int[] $size Registered image size to retrieve the source for or a flat array * of height and width dimensions. Default 'post-thumbnail'. */ return apply_filters( 'post_thumbnail_url', $thumbnail_url, $post, $size );}Changelog
Introduced in 4.4.0. One change between 6.7.7 and 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
$post retyped from int|WP_Post to int|WP_Post|null.verified against sourceAbout this page
- Parsed data
- Generated from the wordpress-develop 7.1.0 tag, from
src/wp-includes/post-thumbnail-template.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.