# headless CMS *Content management system without a front end* A headless CMS stores and edits content but does not render the website. The pages are built by something else, which reads the content over an API — so the editing tools and the front end can be changed independently of each other. **Canonical:** https://spoko.space/glossary/headless-cms/ **Language:** en **Category:** Technology **Also known as:** headless, decoupled CMS, CMS as an API **Published:** 2026-09-22 **Glossary:** https://spoko.space/glossary/ --- ## What it is {#what-it-is} An ordinary CMS does two jobs: it holds the content and it draws the pages. A headless one does the first and stops. The content goes out over an API, and whatever builds the site — a static generator, an app, a mobile client — reads it from there. The word describes an arrangement, not a product. WordPress is a headless CMS the moment you stop using its themes and start reading its REST API, which is the version I meet most often. ## Why it matters if you are paying for a website {#why-it-matters-if-you-are-paying-for-a-website} Because it lets you keep the part people are trained on and replace the part that is slow. The editor stays where it was — same login, same screens, same workflow — and the pages get rebuilt by something that produces plain HTML. That is the whole pitch, and it is a genuine one. It is also where most of the disappointment comes from, so the next section matters more than this one. ## What breaks, from doing it {#what-breaks-from-doing-it} Everything the CMS used to do *while rendering* now has no home, and each piece has to be rebuilt deliberately: **Preview.** "View draft" worked because the CMS drew the page. Once it does not, preview is a feature someone has to build. **Forms.** The contact form was a plugin that rendered a form and received the post. Now the front end owns the form and something else has to receive it. **SEO output.** The meta tags, the canonical, the sitemap, the schema — most of that came from an SEO plugin that injected it into the theme's ``. None of it reaches a front end that never loads the theme, and rebuilding it is not optional. **Plugins in general.** Anything whose value was "it appears on the page" is gone. Anything whose value is "it manages data" survives. I have run this both ways. On one project WordPress stayed exactly as it was and only the front end moved; on another the catalogue moved into a purpose-built admin, because the content model had outgrown what posts and custom fields could express without a diagram. ## What a headless CMS is not {#what-a-headless-cms-is-not} It is not automatically faster — it is the *static build* in front of it that is fast, and a headless CMS read live on every request can be slower than the theme it replaced. It is also not "no CMS": somebody still edits the words somewhere, and pretending otherwise is how a site ends up needing a developer to fix a typo. ## Related terms {#related-terms} - [SSG](https://spoko.space/glossary/ssg/): Static site generation builds every page into a finished HTML file before anyone visits, so a request is answered by a file server instead of by code, a database query and a template rendered on the spot. — Markdown: https://spoko.space/glossary/ssg.md - [Astro](https://spoko.space/glossary/astro/): Astro is a web framework that renders pages to HTML at build time and ships no JavaScript unless a component asks for it. Interactive pieces are declared one by one as islands, so a page carries the code for those and nothing else. — Markdown: https://spoko.space/glossary/astro.md - [CMS](https://spoko.space/glossary/cms/): A CMS is the software that lets someone change a website without touching code. The word covers three separate jobs — editing, storing and displaying content — and most arguments about which CMS to use are really arguments about which of the three you need. — Markdown: https://spoko.space/glossary/cms.md - [Laravel](https://spoko.space/glossary/laravel/): Laravel is a PHP framework for building web applications — the kind with accounts, permissions, a database and work that runs in the background. It supplies the parts every application needs so they are not rebuilt by hand on each project. — Markdown: https://spoko.space/glossary/laravel.md ## Where I write about this {#related-posts} - [Custom CMS with AI](https://spoko.space/custom-cms-with-ai/) — Markdown: https://spoko.space/custom-cms-with-ai.md A custom headless CMS and content dashboard for managing websites, pages, translations and media from a single interface — with AI connected to the content workflow over MCP. - [Enhanced WP REST API Plugin](https://spoko.space/enhanced-wp-rest-api/) — Markdown: https://spoko.space/enhanced-wp-rest-api.md Open-source WordPress plugin extending REST API for headless CMS. Adds GA4, Polylang hreflang data, relative URLs and headless mode with 301 redirects. - [Web application vs website — what is the difference?](https://spoko.space/blog/web-application-vs-website/) — Markdown: https://spoko.space/blog/web-application-vs-website.md A website presents content. A web application lets the user do something. See the differences, when to choose which, and how much each costs. - [Web Application Frameworks in 2026](https://spoko.space/blog/web-application-frameworks-2026/) — Markdown: https://spoko.space/blog/web-application-frameworks-2026.md Astro, Vue, React, Next.js or headless WordPress? A practical comparison of the popular frameworks with performance benchmarks and usage scenarios. ## See also {#see-also} - [Web development](https://spoko.space/web-development/) - [Moving a site off WordPress to Astro](https://spoko.space/wordpress-to-astro/) ## Sources {#sources} - [WordPress REST API Handbook](https://developer.wordpress.org/rest-api/) — What WordPress exposes when it is used as the content store alone. - [Rendering on the Web](https://web.dev/articles/rendering-on-the-web) — Where a decoupled front end sits among the rendering strategies.