Updating post meta data in WordPress using the update_post_meta function

The update_post_meta function in WordPress is used to update the meta data of a specific post. This can be useful for dynamically updating and managing additional information associated with a post, such as custom fields, tags, or other metadata.

By using the update_post_meta function, developers can easily modify the meta data of a post without having to manually edit the database. This can streamline the process of managing and updating post meta data, making it more efficient and less error-prone.

Parameters for update_post_meta function

  • $post_id (int, required): Post ID.
  • $meta_key (string, required): Metadata key.
  • $meta_value (mixed, required): Metadata value. Must be serializable if non-scalar.
  • $prev_value (mixed, optional, default: ”): Previous value to check before updating. If specified, only update existing metadata entries with this value. Otherwise, update all entries.

Return value

int|bool: Meta ID if the key didn’t exist, true on successful update, false on failure or if the value passed to the function is the same as the one that is already in the database.


How to update post meta with a single value

Use the update_post_meta function to update a single value for a specific post.

$post_id = 123;
$meta_key = 'my_custom_field';
$meta_value = 'new_value';

update_post_meta( $post_id, $meta_key, $meta_value );

How to update post meta with an array of values

Use the update_post_meta function to update multiple values for a specific post using an array.

$post_id = 123;
$meta_key = 'my_custom_field';
$meta_value = array( 'value1', 'value2', 'value3' );

update_post_meta( $post_id, $meta_key, $meta_value );

How to update post meta conditionally

Use the update_post_meta function within a conditional statement to update a post meta value based on a certain condition.

$post_id = 123;
$meta_key = 'my_custom_field';
$new_meta_value = 'new_value';

if ( $some_condition ) {
 update_post_meta( $post_id, $meta_key, $new_meta_value );


In conclusion, the update_post_meta function is an essential tool for developers working with WordPress. It allows for easy manipulation of post metadata, providing a seamless way to update and manage data associated with posts. By using this function, developers can efficiently customize and enhance the functionality of their WordPress websites. With its straightforward syntax and flexibility, update_post_meta is a valuable asset for any developer looking to streamline their workflow and improve the user experience on their WordPress sites.

Related WordPress Functions