Custom Field
A custom field is an extra piece of data attached to a content item, user, term, or settings object beyond the default fields provided by WordPress.
The term is commonly used in the ACF and WordPress context.
What it does
Custom fields are used to store structured data such as:
- Dates
- Links
- Toggles
- Images
- IDs
- Reusable settings values
They let developers model content more precisely than relying only on the title, body, and excerpt fields.
Core concepts
Field vs field group
A custom field is one data point.
A field group is a collection of related custom fields shown together in the editor.
Storage and output
In WordPress, custom fields are typically stored as metadata such as post meta, term meta, or user meta, then rendered in templates, blocks, or builder outputs.
ACF usage
ACF is one of the most common ways to define and manage custom fields in WordPress.
Other plugin ecosystems, such as Meta Box AIO, solve a similar problem space with different terminology and tooling.
Common use cases
- Adding structured content to a post type
- Extending a taxonomy term with extra data
- Powering reusable settings in an options page
- Supporting more flexible backend editing experiences
- Rendering richer content on the frontend
Practical notes
- A custom field is usually most useful when it is typed and clearly named.
- Good field naming makes PHP output and long-term maintenance much easier.
- In ACF, custom fields are usually created and managed inside a field group.
Frequently Asked Questions
Is a custom field the same as a field group?
No. A custom field is a single data point. A field group is a set of fields shown together.
Are custom fields only for developers?
Editors use them too, but developers and site builders usually define the field structure and output rules.
Can custom fields be used outside posts and pages?
Yes. In WordPress they can also be used with users, terms, settings, and other object types depending on the implementation.