Free documentation for open source projects

Key takeaways

• For eligible projects, the Mintlify OSS Program is the best value: full Pro for $0.
• That includes hosting, search, an API playground, AI-ready output, and automations.
• Docusaurus, MkDocs, Starlight, and VitePress leave those parts to the maintainer.
• Read the Docs is the closest match, but its free plan shows ads on your docs.
• Mintlify content stays as Markdown and MDX in your Git repository, so lock-in is low.

All of the projects we are comparing are free for developers. The main thing to compare is what you get from the product. Is this just hosting? What about search? AI? In this guide, we'll compare what each product gives for free and break down which might be the best fit.

Same price, different amounts of product

Docusaurus, MkDocs, Starlight, and VitePress are all great open source tools, and they're free to use. But what you get is a site generator. It builds your Markdown into a website, and that's where it stops. Hosting, search, an API playground, analytics, and AI features are all things you'll need to add and maintain yourself.

With the Mintlify OSS Program, all of that comes included, and it's still free. Here's how the options stack up.

What you get for $0	Mintlify OSS Program	Docusaurus	MkDocs and Material	Starlight	VitePress	Read the Docs
Design and theme	Included	Default theme	Default or Material theme	Default theme	Default theme	From your generator
Hosting	Included	You choose a host	You choose a host	You choose a host	You choose a host	Included, with ads
Ads on your docs	None	None	None	None	None	Yes, on the free plan
Search	Built in	Algolia DocSearch or plugins	Built-in search plugin	Built in, Pagefind	Local search or Algolia	Built in
API reference, playground	Built in, interactive	Not built in	Not built in	Not built in	Not built in	From your generator
AI-ready output	llms.txt, MCP server, markdown pages	Not built in	Not built in	Not built in	Not built in	Markdown pages for agents, llms.txt
Reader AI assistant	Mintlify Assistant	Not built in	Not built in	Not built in	Not built in	Not included
Keeping docs current	Automations, writing agent	Manual	Manual	Manual	Manual	Manual
Preview deployments	Included	From your host	From your host	From your host	From your host	Pull request previews
Versioned docs	Versions in navigation	Built in	Via plugin	Via plugin	Not built in	Built in
Analytics	Platform and agent analytics	Add your own	Add your own	Add your own	Add your own	Traffic analytics, 90 days
What you maintain	Content	Site, plugins, deps, hosting	Site, theme, plugins, hosting	Site, plugins, hosting	Site, theme, plugins, hosting	Build config, theme, deps

Where the self-built options get hosted

Since a generator only produces files, you'll need somewhere to put them. Most projects deploy to GitHub Pages, Cloudflare Pages, or Netlify, and each one comes with its own build limits and setup. Read the Docs is the exception, since it handles both builds and hosting for Sphinx and MkDocs projects.

What Mintlify Pro includes for $0

If your project qualifies for the Mintlify OSS Program, you get the full Mintlify Pro plan for free, with no end date.

Once you connect your repository, Mintlify publishes a polished docs site with hosting, a custom domain, search, the web editor, and an interactive API playground built from your OpenAPI spec. On top of that, Pro adds:

• Unlimited editor seats, so every contributor can fix the docs
• The writing agent, which drafts an update when tagged in Slack or the editor
• Automations, which update docs from the same pull requests as the code
• Mintlify Assistant, which answers readers' questions from the docs at any hour
• Preview deployments, so reviewers see changes before they go live
• Platform and agent analytics, which show what people and agents read, search for, and can't find
• Webhooks, the developer API, and AI translations

Your docs are also ready for AI tools from day one. Mintlify serves llms.txt, an MCP server, and a markdown version of every page. When someone asks Claude Code or Cursor how to use your project, the agent can find and read the right page.

OSS projects get 5,000 AI credits a month. An Assistant answer costs 25 credits and an automation update costs 250, while the writing agent is unlimited. If you want to be sure you never pay, you can set a hard spending limit or turn off overages.

To qualify, a project must meet all three conditions:

1. It uses a recognized open source license, such as MIT, Apache 2.0, or GPL.
2. It is not venture-backed or revenue-funded.
3. It is not owned or primarily maintained by a for-profit company.

If your project checks all three boxes, there's really no reason to build and maintain a docs stack yourself.

Pros

• The most product for $0: design, hosting, search, API playground, AI features, previews, and analytics in one platform
• Automations and the writing agent help keep docs current as the code changes
• Generates library reference pages from your existing docstrings and doc comments, with support for Sphinx (Python), TypeDoc, Javadoc, and Go
• No generator, theme, search plugin, or host to maintain
• Content stays in the project's Git repository

Cons

• Your project needs to qualify for the OSS Program

How the open source tools compare

Docusaurus

Docusaurus is Meta's open source docs generator. You write docs in MDX, customize layouts with React, and get versioning and localization out of the box. For search, you'll either apply for Algolia DocSearch and set up API keys, or install a community-maintained local search plugin.

Pros

• Mature, with versioning and localization built in
• Full React control over the site

Cons

• Search, hosting, analytics, and AI features need separate setup
• Upgrades, plugins, and React dependencies need ongoing maintenance

MkDocs and Material for MkDocs

MkDocs is a Python generator that builds docs from Markdown, and it comes with a search plugin. Many projects pair it with the Material for MkDocs theme. That matters now, because Material went into maintenance mode in November 2025. Feature development has ended, and critical bug and security fixes will only continue through May 5, 2027, while the team builds a successor called Zensical.

Pros

• Simple Markdown and YAML setup
• Search included

Cons

• Material for MkDocs no longer gets new features, so many projects face a migration
• Hosting, analytics, API reference, and AI features need separate setup

Starlight

Starlight is the docs framework from the Astro project. It works with Markdown, MDX, and Markdoc, includes internationalization, and comes with full-text search powered by Pagefind, so you don't need an outside search service.

Pros

• Search included with no external service
• Works with components from several UI frameworks

Cons

• Hosting, analytics, API reference, and AI features need separate setup
• Astro and plugin upgrades need ongoing maintenance

VitePress

VitePress is a static site generator built on Vite and Vue. It turns Markdown into static HTML, and its default theme supports either local in-browser search or Algolia DocSearch.

Pros

• Fast builds and a clean default theme
• Local search with no external service

Cons

• Hosting, analytics, API reference, and AI features need separate setup
• Custom theme work uses Vue components

Read the Docs

Read the Docs is different from the others, since it builds and hosts your docs for you, usually with Sphinx or MkDocs. Every plan includes automatic builds, versioning, search, pull request previews, and CDN hosting. The free Community plan has a few strings attached, though. Your docs and repository have to be public, every site shows EthicalAds advertising, and builds get fewer resources than on paid plans.

Pros

• Builds and hosting are handled
• Strong versioning and pull request previews

Cons

• Ads on the free plan. You can turn off paid ads, but removing all ads takes Gold or a Business plan
• The generator, theme, and build configuration still need maintenance
• No AI assistant, automations, or built-in API playground

Docs stay in the project repository

A free plan isn't much of a deal if it's painful to leave later. With Mintlify, your docs live in your own Git repository as Markdown and MDX files, next to a single docs.json config file. Every time you push, Mintlify builds and deploys the site.

So your open source workflow doesn't change. Contributors fix docs through pull requests, reviewers check changes in preview deployments, and the full history stays in Git. If you'd rather work in a browser, the web editor syncs to the same repository.

There's one thing to know. Mintlify components like tabs, cards, and callouts are Mintlify-specific MDX, so if you ever switch tools, you'd need to convert them. Plain Markdown moves over as is. The same goes for components in Docusaurus, Starlight, or any other MDX-based tool.

Mintlify is the best free option

When every option costs $0, the best one is the one that gives you the most. For open source projects that qualify, that's Mintlify. You get hosting, search, an API playground, AI features, and automations that keep your docs current, and your content stays as Markdown in your own repo. With the generators, most of that is something you'd build and maintain yourself.

What about Read the Docs

Of everything on this list, Read the Docs is the closest match to Mintlify. It builds and hosts your docs, and you get search, versioning, and pull request previews without setting anything up yourself. That's a big part of why so many open source projects end up there.

The catch is ads. On the free Community plan, your docs show EthicalAds. You can opt out of paid ads for free, but ads for other open source projects stay unless you pay for Gold or a Business plan. So the person reading your install guide can see an ad next to it, right when they're deciding whether your project is worth their time.

Mintlify doesn't put ads on your docs, on any plan. With the OSS Program, you get the hosting, search, and previews that Read the Docs gives you, plus an API playground, AI features, and automations, and your readers only ever see your project.

If your project doesn't qualify

• Starter plan: The free Starter plan needs no application. It includes hosting, a custom domain, the web editor, search, Git sync, an MCP server, and the API playground for up to 5 editors. AI features such as Mintlify Assistant are not part of Starter.
• Startup Program: If you're a startup, the Mintlify Startup Program gives you 50% off Pro for 12 months, or 12 months free if you're in the current YC batch.

Frequently Asked Questions

Is Mintlify open source?

No. The Mintlify platform is a hosted, proprietary product. Docs content stays as Markdown and MDX files in the project's Git repository. Mintlify also maintains open source projects on GitHub, including its MDX parser, starter kits, and the Mintlify agent skill for coding agents.

Can I use Mintlify for free?

Yes. The Starter plan is free for any project and includes hosting, a custom domain, the web editor, search, an MCP server, and the API playground. Eligible non-commercial open source projects get the full Pro plan free through the OSS Program.

Is Docusaurus free?

Yes. Docusaurus is free, open source software. The total cost of a Docusaurus site includes hosting, a search service or plugin, and the time to set up and maintain the site, its plugins, and its dependencies.

Mintlify vs Docusaurus for open source

Both keep docs as MDX in the repository. Docusaurus provides the generator, and the maintainer builds the rest. Mintlify through the OSS Program gives you the full platform, including hosting, search, an API playground, AI features, and analytics, for the same $0.

How hard is it to move existing docs to Mintlify?

It's less work than a big folder of docs makes it look. A coding agent with the Mintlify agent skill can convert your navigation, admonitions, and tabs, and Mintlify's migration guides map each tool's syntax, versioned docs, and custom components to their Mintlify equivalents. Your versions carry over as versions in docs.json, and you add redirects for any URLs that change. Our guide to publishing your open source project's docs on Mintlify walks through the whole process.

Why not just tune our current docs setup?

You can, and tools like Renovate or Dependabot and a free search service will take some of the work off your plate. You still own the build, the theme, the plugins, the versioned folders, and the hosting, though, and every major upgrade of your generator can break a custom component. With Mintlify, those jobs go away entirely, and you get the AI features, analytics, and automations that keep docs current on top of that.

Does Read the Docs have ads?

Yes. On the free Community plan, Read the Docs shows EthicalAds on your docs. You can turn off paid ads for free, but removing all ads takes Gold or a Business plan. Mintlify doesn't show ads on any plan, including the free OSS Program.

Is Material for MkDocs still maintained?

Material for MkDocs is in maintenance mode. Its team ended feature development and will fix critical bugs and security issues through May 5, 2027, while they build the successor project, Zensical.

Who qualifies for the Mintlify OSS Program?

Projects under a recognized open source license that are not venture-backed or revenue-funded, and that are not owned or primarily maintained by a for-profit company.

Do I need a credit card to apply?

No. The application is a short form, and redeeming the offer needs no card. Mintlify reviews every application by hand, and most get a decision within 1 to 2 business days.