Short answer
A headless CMS stores content without controlling how it is displayed: editors work in an admin interface, and the content is delivered to a website, mobile app or in-store screen through an API. Contentful, Sanity and Strapi are examples. The front end is built separately, which is both the cost and the point.
Also called: Decoupled CMS, API-first CMS
The design assumption is that content outlives presentation. A product description written once should be able to appear on a website, in an app and inside a printed catalogue without being retyped, which is why headless systems store structured fields rather than formatted pages. That structure is also what makes content readable by machines — the same discipline that makes a passage extractable by an answer engine.
The cost is that nothing is included. A traditional CMS ships with themes and a preview; a headless one ships with an empty API, and the display layer, the preview and the editorial workflow all have to be built. For a single website with one editor, that is usually more machinery than the job needs. For several channels sharing one content library, it stops being overhead and starts being the reason the project is feasible.
Where this comes up in our work
Related terms
Content Management System (CMS)
A content management system is software that lets non-technical staff create, edit and publish website content without touching code.
API (Application Programming Interface)
An API is a defined way for one piece of software to request data or actions from another: a checkout asking a payment gateway to take a GCash payment, or a dashboard pulling yesterday’s sales from an accounting system.
Server-Side Rendering (SSR) vs Static Site Generation (SSG)
Server-side rendering builds each page when a visitor requests it, so the content reflects the database at that moment.
Custom Software vs Off-the-Shelf Software
Custom software is built for one organisation’s specific process; off-the-shelf software is a finished product many organisations subscribe to, such as Shopify or QuickBooks.
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