What “open source” changes—and what it does not
An open source content management system gives teams the right to inspect, run and modify software under its license. That can reduce platform lock-in and make self-hosting possible. It does not guarantee a free project, an easy migration or unlimited compatibility between extensions.
Start by verifying the exact license and edition. Some vendors combine an open community edition with paid cloud services or enterprise features. Then examine who maintains the project, how security notices are published and whether your team can operate the chosen stack.
Open source CMS comparison
| CMS | Model | Stack | License | Best fit |
|---|---|---|---|---|
| WordPress | Traditional / hybrid | PHP | GPLv2 or later | Publishing, marketing sites, broad plugin needs |
| Drupal | Structured / hybrid | PHP | GPL-2.0-or-later | Complex content models, permissions and large organizations |
| Joomla | Traditional | PHP | GPL-2.0-or-later | Portals, multilingual sites and structured publishing |
| Ghost | Publishing / headless | JavaScript | MIT | Newsletters, memberships and focused publications |
| Strapi | Headless | JavaScript / TypeScript | MIT (community edition) | Custom apps needing an API-first editorial backend |
| Grav | Flat-file | PHP | MIT | Fast documentation, portfolios and smaller content sites |
Licenses and product terms can change. Follow each project link and confirm the terms that apply to the version and edition you plan to deploy.
Choose by operating model
Traditional publishing
WordPress, Drupal and Joomla render complete websites and provide established editorial administration. They are practical when the primary channel is the web and a theme-based delivery model is acceptable.
API-first delivery
Strapi and similar headless platforms expose structured content for multiple frontends. Your team must supply the website or application layer, preview workflow, caching and deployment pipeline.
Flat-file simplicity
Grav stores content in files instead of a relational database. It can be a clean fit for smaller sites and developer-owned documentation, but it is not a universal replacement for complex editorial operations.
Shortlist checklist
- Confirm license obligations and commercial edition boundaries.
- Test an editor’s most common task, including preview and revisions.
- Model one difficult content type—not just a blog post.
- Document updates, backups, monitoring and incident ownership.
- Export representative content before committing to the platform.
Frequently asked questions
Is open source CMS software free?
The code may be available without a license fee, but hosting, development, design, maintenance, security and migration still carry costs.
Which open source CMS is best?
There is no universal best option. WordPress suits broad publishing needs, Drupal is strong for complex structured content and permissions, while headless platforms suit API-first delivery.
Can an open source CMS be secure?
Yes, when supported versions, trusted extensions, least privilege, patching, backups and monitoring are managed well. Open source status alone does not determine security.