get_the_ID() │ WP 2.1.0

Retrieve the ID of the current post in the WordPress Loop. Can be used only inside the loop.

Post ID in the loop can be also obtained through $post->ID. Sometimes it's easier and there is no unnecessary call of the function.

Uses: get_post()
Used By: the_ID()
1 time — 0.000037 sec (very fast) | 50000 times — 0.28 sec (very fast) | PHP 7.1.2, WP 4.7.3

No Hooks.

Return

Int|false. The ID of the current item in the WordPress Loop. False if $post is not set.

Usage

get_the_ID() // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionNameInvalid;

Examples

0

#1 Get the post ID

Usually the post ID inside the loop can be obtained through $post->ID, but in some cases it may be useful to get it like this:

$post_id = get_the_ID();
// $post_id will contain the ID of the current post in the loop
0

#2 Display the meta field of the post using the get_the_ID() function: 

$post_id = get_the_ID();
echo get_post_meta( $post_id, 'meta_key', 1);

// or can be so:
echo get_post_meta( get_the_ID(), 'meta_key', 1);

Changelog

Since 2.1.0 Introduced.

Code of get_the_ID() WP 5.9.3

wp-includes/post-template.php 
function get_the_ID() { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionNameInvalid
	$post = get_post();
	return ! empty( $post ) ? $post->ID : false;
}

WP Loop

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