WordPress has the ability to allow post authors to assign custom fields to a post. This arbitrary extra information is known as metadata. This metadata can include bits of information such as:
- Mood: Happy
- Currently Reading: Cinderella
- Listening To: Rock Around the Clock
- Weather: Hot and humid
With some extra coding, it is possible to achieve more complex actions, such as using the metadata to store an expiration date for a post.
Metadata is handled with key/value pairs. The key is the name of the metadata element. The value is the information that will appear in the metadata list on each individual post that the information is associated with.
Keys can be used more than once per post. For example, if you were reading two different books (perhaps a technical book at work and a fiction at home), you could create a “reading” key and use it twice on the same post, once for each book.
Here is an example of what this information might look like on your post:
Currently Reading: Calvin and Hobbes
Today's Mood: Jolly and Happy
Based upon our example above, let’s add two custom fields, one called “Currently Reading” and the other “Today’s Mood”. Please follow the below steps to add this information to a post using Custom Fields.
- Custom Fields options on the Post & Page edit screens are hidden by default if they have not been used before. Using the Block Editor, click the three dots button at the top of the right sidebar and visit Options to enable it. (If you are using the Classic editor, check the screen options).
- After you have written your post, scroll down to the area titled Custom Fields.
- To create a new Custom Field called “Currently Reading”, enter the text “Currently Reading” (without the quotes) in the text entry field titled Name.
- The newly created Key (“Currently Reading”) should now be assigned a Value, which in our case is the name of the book currently being read, “Calvin and Hobbes”. Type “Calvin and Hobbes” in the Value field, again without the quotes.
- Click Add Custom Field button to save this custom information for that post.
To add your “Today’s Mood”, repeat the process and add “Today’s Mood” to the key and a description of your mood in the value text boxes and click Add Custom Field to save this information with the post.
On your next post, you can add a new book and mood to your metadata. In the Custom Fields section, the Key will now feature a pull-down list with the previously entered Custom Fields. Choose “Currently Reading” and then enter the new book you are reading in the value. Click Add Custom Field and then repeat the process to add “Today’s Mood”.
You only need to create a new “KEY” once, after which you can assign a value to that key for every post, if you so desire. You can also assign more than one Value to a key, for a post. This will come in handy for people who read more than one book at a time.
Displaying Custom Fields
To display the Custom Fields for each post, you have to use a template tag that customizes your theme. For more details about it, please refer to:
- the_meta() – Template tag that automatically lists all Custom Fields of a post
- get_post_custom() and get_post_meta() – Retrieves one or all metadata of a post.
- get_post_custom_values() – Retrieves values for a custom post field.
- Template Tags – WordPress Theme Developers Handbook page on Template Tags
You may install a plugin that manages custom fields by searching “custom fields” in the plugins directory.