wp_is_mobile(): bool
- Since
- 3.4.0, 6.4.0
- Source
wp-includes/vars.php:163
Compatibility
- WordPress
- since 6.4.0
- 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.
Return value
bool- Whether the request is from a mobile device.
Performance profile
How much work a call to wp_is_mobile() 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
- Trivial
- Scaling
- Constant
- Instructions
- 12–41
- Plugin surface
- 1 hook
- Called by
- 9
Touches nothing outside its own arguments.
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 48.
Third-party callbacks on 'wp_is_mobile' run inside this call, and their cost is not bounded by anything here.
9 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
What one call costs · 1 distinct outcome
One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_is_mobile() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 12–41 | apply_filters() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 48 | 12–41 | 9 | |
| 8.5 | 48 | 12–41 | 9 | |
| 8.4 | 48 | 12–41 | 9 | 21 fewer instructions than PHP 8.3 |
| 8.3 | 69 | 12–62 | 9 | |
| 8.2 | 69 | 12–62 | 9 | |
| 8.1 | 69 | 12–62 | 9 | 7 fewer instructions than PHP 7.4 |
| 7.4 | 76 | 12–69 | 9 |
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 wp_is_mobile() runs, in this order:
- apply_filters( wp_is_mobile )filterline 189 (+26 into the body)
Filters whether the request should be treated as coming from a mobile device or not.
Uses · 2
- str_contains()Polyfill for `str_contains()` function added in PHP 8.0.
- apply_filters()Calls the callback functions that have been added to a filter hook.
Used by · 9
- WP_Admin_Bar::_render()
- WP_Customize_Manager::customize_pane_settings()Prints JavaScript settings for parent window.
- WP_Customize_Manager::is_ios()Determines whether the user agent is iOS.
- _WP_Editors::editor_settings()
- _device_can_upload()Tests if the current device has the capability to upload files.
- _wp_customize_loader_settings()Adds settings for the customize-loader script.
- media_upload_form()Outputs the legacy media upload form.
- user_can_richedit()Determines whether the user can access the visual editor.
- wp_plupload_default_settings()Prints default Plupload arguments.
Source code
function wp_is_mobile() { if ( isset( $_SERVER['HTTP_SEC_CH_UA_MOBILE'] ) ) { // This is the `Sec-CH-UA-Mobile` user agent client hint HTTP request header. // See <https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Sec-CH-UA-Mobile>. $is_mobile = ( '?1' === $_SERVER['HTTP_SEC_CH_UA_MOBILE'] ); } elseif ( empty( $_SERVER['HTTP_USER_AGENT'] ) ) { $is_mobile = false; } elseif ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'Mobile' ) // Many mobile devices (all iPhone, iPad, etc.) || str_contains( $_SERVER['HTTP_USER_AGENT'], 'Android' ) || str_contains( $_SERVER['HTTP_USER_AGENT'], 'Silk/' ) || str_contains( $_SERVER['HTTP_USER_AGENT'], 'Kindle' ) || str_contains( $_SERVER['HTTP_USER_AGENT'], 'BlackBerry' ) || str_contains( $_SERVER['HTTP_USER_AGENT'], 'Opera Mini' ) || str_contains( $_SERVER['HTTP_USER_AGENT'], 'Opera Mobi' ) ) { $is_mobile = true; } else { $is_mobile = false; } /** * Filters whether the request should be treated as coming from a mobile device or not. * * @since 4.9.0 * * @param bool $is_mobile Whether the request is from a mobile device or not. */ return apply_filters( 'wp_is_mobile', $is_mobile );}Changelog
Introduced in 3.4.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 7.1.0 tag, from
src/wp-includes/vars.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.