Mintlify alternatives in 2026, with AI answer costs

The Mintlify alternatives most worth weighing in 2026 are GitBook, ReadMe, Fern, Document360 and Docusaurus. GitBook suits product docs written in a visual editor, ReadMe and Fern are built around an API reference, Document360 suits a large knowledge base with many writers, and Docusaurus is free and open source for a team that hosts its own site. Mintlify’s Starter plan is free, but its AI assistant sits on Pro, which is $450 a month billed yearly or $540 monthly. We read every price below on the vendor’s own pages on 19 October 2026, in US dollars, and each one links to where we read it.

Deacon is ours, and it isn’t a docs platform. It’s an AI support agent that answers your visitors from whichever docs you choose, a free self-hosted site included, and tells you what they keep asking for. It has a free plan.

Mintlify and five alternatives side by side

Mintlify is the first row, so each platform can be read against it. The AI column is about answering your readers, not about AI that helps you write.

What Mintlify costs, and what its assistant costs

Mintlify’s pricing page has three plans. Starter is free forever and includes hosting, a custom domain, the web editor, authentication, an MCP server, the API playground and up to 5 editor seats. A new site goes live at a mintlify.site address. Every page is a Markdown file in a Git repository, and Git sync is on every plan.

Pro is $450 a month billed yearly, or $540 monthly, and removes the seat limit. It adds the assistant, a writing agent, automations that update your docs, preview deployments and admin APIs. Enterprise is priced by quote, with SSO, a performance SLA and self-hosting.

The AI is billed in credits. Pro includes 10,000 credits a month, an assistant answer takes 25 and an automation that updates your docs takes 250. Mintlify charges nothing when the assistant can’t answer or an automation finds nothing to change. Past the monthly credits you pay $0.01 a credit, or you can turn overages off so the AI pauses until the next cycle. If the assistant spent the credits on its own, a month’s credits would pay for 400 of its answers, and each answer after that would cost $0.25. The sums are ours.

Mintlify’s assistant docs say it answers only from your documentation, cites the pages it used, and says it doesn’t have enough information when it can’t find the answer. You can give it a support email to offer the reader when that happens. It indexes your changes as soon as you publish them. A widget puts the same assistant on your app or marketing site with a hosted script, on Pro or Enterprise, using the same credits.

There are two ways to pay less. Mintlify’s Startup Program gives 50% off Pro for 12 months to venture-backed startups founded in the last 2 years that have raised under $2M and never paid for Mintlify. Non-commercial open source projects can apply for Pro free. Every new account also gets a 14-day Pro trial with 5,000 credits and no card, and it ends early if the credits run out.

Five docs platforms to weigh instead

Each of these hosts or builds your docs site. They differ most in who writes the docs, how the AI is sold, and what you pay before readers get answers.

GitBook

GitBook sells by the site and by the user. The free plan is for individuals, with the block editor, GitHub or GitLab sync, interactive API docs and an MCP server for your docs. Essential is $65 a site a month billed yearly, plus $12 for each user, and adds a custom domain, your team, analytics and Assistant Ask. Ultimate is $249 a site a month billed yearly, plus $12 a user, and adds Assistant Chat, a chat sidebar that GitBook describes as helping users “find, understand, or take action on your docs”.

The AI runs on credits. Essential includes $20 of AI credits a month, which is 2,000 credits, and Ultimate includes $100, which is 10,000. Each relevant question takes 20 credits, so Essential’s monthly credits cover about 100 questions, by our sum. When the credits run out, the AI pauses, and more can be bought in monthly bundles. Embedding the Assistant in your own site or product, connecting sources such as GitHub and Slack, and insights into what it answered all start on Ultimate. Pick GitBook if non-developers write your docs alongside engineers.

ReadMe

ReadMe is built for API documentation. Its Starter plan is free and includes a custom domain, bi-directional sync, an interactive API reference, usage metrics and an MCP server. Pro is $250 a month billed yearly, with a 14-day trial of every Pro feature, and adds teammates, branching and reviews, private docs, a landing page, a changelog, recipes and forums.

ReadMe’s Ask AI docs explain its two levels. Ask AI Lite comes with Pro and Enterprise and answers from your published docs with links to the source pages. The full Ask AI is an add-on on any plan at $150 a month, and adds control of tone, answer length and forbidden topics, a choice of model, and analytics of what readers ask. ReadMe says both give answers of the same quality, and the add-on buys the controls. Pick ReadMe if your docs are mostly an API reference and you want readers to try calls from the page.

Fern

Fern sells documentation sites and client SDKs for APIs. Its pricing page has a free plan and an Enterprise plan, with nothing in between. Free is free forever, for 10 team members and 1,000 pages, with a custom domain or subpath, guides, API references and changelogs, the API explorer and web editor, and 250 AI credits a month. Enterprise is priced by quote and adds SSO, several repositories, custom React components, advanced analytics and self-hosting.

Ask Fern is on the free plan. It’s a side panel on your docs that answers from them with citations to the source pages. It can also answer in Slack, and its widgets embed in any React app. Fern’s dashboard shows each conversation with a verdict of Resolved or Unresolved once a model has judged it, and you can filter for the unresolved ones to find gaps in your docs. Pick Fern if you also want Fern to build your SDKs.

Document360

Document360 is a knowledge base for large, carefully structured documentation, with categories, templates, review reminders and approval workflows. Its pricing page publishes no prices. It asks what you’re building and quotes on team accounts, workspaces, languages, security, privacy and use of its AI Premium Suite, and says a flat tier “would either overcharge small teams or undercharge enterprises”. There’s a 14-day free trial of every feature.

AI search and answers come with the plan as part of Eddy AI. The AI chatbot, which answers from your knowledge base, websites, files, FAQs and Zendesk or Freshdesk tickets, is an add-on. Pick Document360 if you have many writers and many articles and are happy to take a quote. The best knowledge base software ranks it among eight tools for a customer help centre.

Docusaurus

Docusaurus is a static site generator built on React, made for documentation, and released under the MIT licence. You write pages in Markdown or MDX, build the site yourself and publish it to GitHub Pages, Netlify, Vercel or another host. The software costs nothing. The work is yours, from the build to the design.

There’s no AI assistant built in. Docusaurus’s search guide supports Algolia DocSearch, which is free for developer documentation and technical blogs through an application to the DocSearch program. DocSearch’s Ask AI answers questions about your docs from the search box. The guide calls it “available at no additional cost”, and you pay your own model provider for what it uses. Pick Docusaurus if you have a developer who’d rather own the site than pay for one. Adding an AI chatbot to a GitHub Pages site shows where a script tag goes on a Docusaurus site built there.

Keep your docs where they are and add AI answers on top

A docs platform does two jobs. It hosts the pages, and, usually on a paid plan, it answers readers from them. Those can come from different places. A free Docusaurus site, or Mintlify’s free Starter, can hold the docs while something else answers the questions.

That matters when the questions start away from the docs. A buyer asks on your pricing page, and a customer gets stuck in your app and never opens the docs at all. Mintlify’s widget and GitBook’s embed reach those places too, on Pro and on Ultimate. An AI agent that goes on every site you run gives the same answers in all of them, from whatever docs you write, and keeps the questions in one list.

What to look for in a documentation AI assistant sets out the choices and six tests to run before readers see one.

What Deacon adds to any docs platform

Deacon doesn’t host docs, write an API reference or sync with your repository. It reads the public pages you already publish, wherever they’re hosted, along with files you upload and answers you write, and the knowledge base chatbot page shows how. Readers get an answer from your docs in seconds, or, when the docs are silent, Deacon saying it doesn’t know, with a box for their email. What Deacon adds on top is what those readers’ questions say about your docs and your product.

Here’s how that plays out on a docs site.

• A missing page that’s really a missing feature. When readers keep asking for a Terraform provider or a webhook you don’t send, no page can answer, because the product doesn’t do it yet. Topics gather those questions, count the people asking and mark a group as a feature ask or a bug report when that kind leads it, and Analytics › Widget lists what readers ask you to build, quoted as they typed it. With enough questions to go on, it also names the docs page whose questions go unanswered more often than the rest.
• The page that sends people to the chat. Analytics › Website lists your most visited pages, each with the questions asked on it beside its visits and how many went unanswered. A quickstart that drew twenty questions a week would stand out beside reference pages that drew none. Conversations has an Unanswered filter for the questions no page covered.
• An answer written once, outside your docs platform. What needs you lists what Deacon didn’t know, each a click from a box for your answer. The answer goes into Deacon’s own help document, so there’s no pull request or redeploy, and Deacon answers from it straight away. It shows the reply a reader would now get and any other open questions the same answer covers. The help document downloads as Markdown when you want to move those answers into your docs.
• A marketing site made with an AI app builder. Install is one script tag, with its own steps for Lovable, Bolt, Replit and Base44. A landing page from Bolt and docs on Mintlify can share one Deacon that answers from the same knowledge, and adding Deacon to a Bolt site shows that install.

One listed domain covers its subdomains, so example.com covers docs.example.com and app.example.com. Docs on another address, such as a mintlify.site site, need an entry of their own.

Which Mintlify alternative fits you

Start with who writes your docs and what you’d pay before readers get AI answers.

If you want one vendor for hosting, AI answers and a writing agent, and have the budget, Mintlify’s Pro does all three, and its startup discount takes half off for a year if you qualify. If people outside engineering write the docs, GitBook’s editor suits them, and AI answers start on Essential. If your docs are mostly an API reference, ReadMe and Fern are built for it, and Fern’s free plan already answers readers with AI. If you have hundreds of articles and many editors, Document360 goes deepest, on a quote. If you have a developer and would rather pay nothing, Docusaurus is free, and you add search and AI yourself.

If you answer support yourself, you can also keep your docs on a free plan and put Deacon on your docs, your app and your marketing site. How to set up an AI chatbot for documentation walks through choosing the pages and testing it.

Questions about Mintlify alternatives

Is there a free Mintlify alternative?

Yes, several. Docusaurus is free and open source, and you host it. Fern’s free plan hosts your docs and includes Ask Fern with 250 AI credits a month. ReadMe’s Starter is free with a custom domain, and GitBook has a free plan for individuals. Mintlify’s own Starter is free too, for up to 5 editors, without its AI features.

Does Mintlify’s AI assistant cost extra?

It comes with Pro, at $450 a month billed yearly, and isn’t on Starter. Each answer takes 25 credits from Pro’s 10,000 a month, an answer it can’t give costs nothing, and extra credits are $0.01 each. You can turn overages off so the assistant pauses at the limit instead.

Can I move my docs off Mintlify?

Mintlify keeps every page as a Markdown file, .mdx or .md, in a Git repository, and you can move that repository to your own GitHub or GitLab account. So you keep the pages whichever platform you go to. Docusaurus also takes MDX, and Mintlify has tools to move docs in from ReadMe and Docusaurus.

Can I add Deacon to docs hosted on Mintlify?

Mintlify runs any .js file in your docs folder on every page, and its custom scripts guide shows how to load a third-party script from one. So a short .js file that adds Deacon’s script tag puts Deacon on every page. Mintlify’s pricing table lists custom CSS and JS on every plan. Add the docs address on Deacon’s Install page unless it’s a subdomain of a site you’ve already listed.

Is Deacon a documentation platform?

No. Deacon doesn’t host or publish docs, and has no editor, API reference or Git sync. It’s an AI support agent that answers visitors on your website from pages it reads there, files you upload, text you paste and answers you write. You keep your docs on whichever platform you choose, a free one included.

Will Deacon notice when I change my docs?

Not by itself. Deacon re-reads a page when you fetch it again, one page at a time, and the new version usually answers as soon as it’s read. No timer fetches your pages for you. This is one place a platform’s own assistant does better. Mintlify’s indexes your changes as soon as you publish them.