Over the last ten years, I’ve pivoted my career a few times. I started as a developer, then as a technical writer, then as a documentation engineer, then as a developer educator, and then, most recently, as a documentation engineering manager.
I started consulting for Copytree, a technical writing agency, and we get questions all the time from clients and other prospects about which documentation platform they should use. I couldn’t find a comprehensive comparison out there, so I wrote this article combining both my first-hand experience, what the platforms say about themselves, and what other people are saying online.
I’m sure I’ll make some mistakes, and I welcome corrections and disagreements, so please email me at andrew@copytree.io if I’ve missed anything!
I'm excited to share that Nordic APIs is hosting a condensed version of this article on their blog!
Check out the article! https://nordicapis.com/review-of-4-modern-documentation-platforms/
A documentation platform is a product that provides capabilities—some free; some paid—for a range of activities, like authoring, editing, collaborating, monitoring, building, deploying, and publishing documentation.
Docs-as-code platforms are more common these days, as more people can code or leverage systems like AI that help them code. Traditionally, authoring to publication might take place locally, or via a software product that offered manual versioning, limited collaboration, and limited-to-no support for documentation pipeline automation, like setting up a CI/CD pipeline to deploy health documentation when the `main` has a new commit. If you remember the yesteryears of authoring, products like Subversion and TortoiseSVN may come to mind.
The platforms I’m writing about today are modern and all offer some type of free documentation generation, usually through static site generation; however, outside of what’s provided out of the box, there are notable differences between what’s provided for free and what’s provided at cost.
My goal for this article is to point out some core differences across add-ons, features, and enterprise-level support across these documentation platforms so that you choose the platform that’s best for you and your documentation readers.
To better understand the differences, I’m focusing on four areas of interest:
API support: What types of API documentation can you create?
Feature support: How do the platforms differ in feature and enterprise support?
Artificial intelligence: What features leverage AI, if any?
Analytics: How can you measure documentation success?
As you read through the sections, I encourage you to think about what’s important to you and your documentation authors, maintainers, and readers. What’s important is something that only you know; it’s different for every person, for every product, for every company.
Here are some example questions to get you started:
What features do you need? Do you want features to be powered by AI?
What do your customers need? Guarantees for uptime? Layers of security?
Who’s writing the documentation? Are they technical? Do they need to be?
All four platforms support OpenAPI Specification (OAS) and are capable of generating static site websites, with a WYSIWYG editor experience. Each platform can also test out API calls in the generated documentation.
Fern offers the widest range of support and is the only platform that offers support for OpenRPC. Though Mintlify offers less options, it does offer a free tier of support for OpenAPI definitions and AsyncAPI schemas.
Along those same lines, ReadMe has free entry with OpenAPI and PostMan Collections.
Finally, Redocly is built on top of Redoc open source, so it’s notable to mention that Redoc premium is what you would want for AsyncAPI, GraphQL, or SOAP support. Additionally, SOAP support is only available on Redocly.
For this section, let’s start with an overview of some core features across the platforms. Because of how important the first two features are to authoring and understanding, we’re going to investigate them in more detail.
Editor (GUI)
Fern, Mintlify, and ReadMe all offer “What you see is what you get” (WYSIWYG) editors, Git workflows, and Git synchronization; though, for ReadMe, git features are only available via its Refactored product. Redocly’s editor is a code editor and synchronizes with GitHub, GitLab, Azure DevOps, and its own custom Git product.
If you’re interested in a true, no-git experience, I recommend ReadMe. For a hybrid experience, with a WYSIWYG editor that syncs to git repositories, I recommend Mintlify; for an all-in, docs-as-code writing experience, I recommend Fern or Redocly.
Try-It API
All of these platform experiences are relatively equitable. Each platform lets readers try out requests, though some offer this ability through mock functionality (Mintlify, Redocly) while others offer this ability through real-time authentication (Fern, ReadMe).
Some notable features while trying these products include Fern and ReadMe both auto-populating examples, Mintlify supporting overrides to auto-generation via MDX, and Redocly saving the history of requests via its mock server.
My recommendation is to look at the accompanying features, like the ability for readers to switch environments or the ability for maintainers to have custom ordering of generated documentation, in order to make the best decision for your readers.
Here’s a few highlights from each platform’s enterprise tier documentation.
In terms of pricing, Fern, Mintlify, and Redocly have custom (i.e., negotiable) pricing for enterprise—whereas ReadMe sets its enterprise-level pricing as a defined cost.
Some notable callouts include Fern’s automated testing in CI for production APIs and custom code maintenance, Mintlify’s content backups and “uptime SLA of 99.99%”, ReadMe’s offering of a customer success manager and content writing and design team, and, for Redocly, choice of data storage locations and access to its Sales support team.
In this section, I’m reviewing my exploration of AI features across each platform and the different underlying models that each platform chooses to use for these features. There’s no escaping the AI question in 2025. Every platform needs to have some feature or offering that leverages AI to help documentation authors, maintainers, and readers.
To better understand this section, let’s start by reviewing some concepts. Feel free to skip over anything you already understand.
LLMs.txt: A file, similar in philosophy to robots.txt ⇔ sitemap.xml, that details where a model can find additional context to improve the answers of an AI assistant. LLMs-full.txt is a further abstraction of this idea, providing context for the entire site. All of the platforms we’re discussing today generate this file, usually at the root.
MCP: An open protocol that standardizes how applications provide context to LLMs. Agents interact with live Model Context Protocol (MCP) servers, in an effort to improve AI agent tasks, such as helping readers understand documentation. All of the platforms we’re discussing today include documentation for generating one of these servers; some offer partnerships in building them together.
Ask AI: The ability to interact with an AI assistant that answers free-form questions about documentation content. In the case of the platforms we’re discussing today, this refers to a drop-down context menu to interact with the assistant on documentation pages.
AI Search: The ability to interact with an AI assistant that answers free-form questions about where to find documentation content. In the case of the platforms we’re discussing today, this refers to a selectable version of search powered by the assistant, instead of a more traditional search, typically powered by a built-in indexer or Algolia.
With these concepts reviewed, let’s review the distinction in AI features across these platforms.
This section was really interesting to explore during my research. Every platform offers AI search, yet each platform chooses a different underlying model as part of the implementation. Mintlify seems to offer the most variety in model support, at least as far as what is overtly mentioned in the documentation. I also greatly appreciated Redocly’s transparent documentation on how AI search data is handled.
My recommendation, if you are interested in using any of these AI features, is that you take a very careful read at usage limits on each platform’s pricing page, as there are different cost considerations and limits between the many free and paid plans. With ReadMe, as an example, Owlbot AI is treated as an add-on, instead of part of any distinct paid plan, and is a cost-effective way of experimenting with AI features without dedicating yourself to any of these company’s premium tiers.
One prediction that I have for the near future is that competition will drive many of these AI features (that are now almost universally at-cost) to instead become free and provided out of the box at some level, with a general customer expectation that AI integration is a baseline requirement of free pricing plans.
The last section I’m covering in this article is on documentation analytics and other notable analytics integrations highlighted on each platform’s respective documentation website.
Documentation analytics give authors and maintainers a greater sense of what’s working, what’s not working, what readers are trying, what they’re not trying, and, often, where documentation needs to be created, updated, edited, or, sometimes, even completely removed.
Aside from the information already detailed in the table, here is my opinion on some unique value propositions, according to what’s built-in, from each platform:
Fern: The multi-selection “Was this page helpful” feedback system and integration with Slack and email stands out as a way to get real-time, granular feedback.
Mintlify: The low-confidence searches metric and breadth of integrations stand out as a way to improve bad search outcomes and create a documentation strategy.
ReadMe: The API endpoints dashboard stands out as a way to better understand how developers are using documented APIs.
Redocly: The report icon on code examples and the system logging of the platform and user agent on feedback and reports stand out as a way to improve reliability.
To end this section, I wanted to give a few examples of projects that you might consider as you review analytics on your platform of choice. These are real-world examples inspired by projects that I completed while working professionally in documentation. My experience comes from reviewing Google Analytics, GitHub Insights, and understanding custom events logged in-code to better understand documentation and goal on improving product experience.
Improve search and documentation quality: Using query data from site search, review top X queries over a range of time and focus on mapping top queries to targeted documentation pages and, over time, change the way that readers search for documentation across the website both by understanding entry points into documentation pages and where foundational understanding is lacking, according to inadequate, or just completely non-existent, introductory copy and documentation.
Reduce errors and crashes: Using page traffic data, and a combination of other information, like search and crash data, where available, review individual pages and segments of documentation focused on helping readers debug and fix errors, and combine this analysis with a strategy of creating and improving anchor tag sections across documentation pages, like in Troubleshooting or FAQ, to drive down specific error messages and reduce overall product crashes by changing behavior through higher-quality documentation.
Answer customer questions: Using page referral data, follow trails of documentation links across the web to active discussions on forums, like GitHub and Bluesky, where you can answer questions, capture feature feedback, and help onboard customers to a product or feature through posts, DMs, or just general promotion of new and revised onboarding documentation.
Here are my final recommendations. As always, choose what works best for you, your documentation authors, maintainers, and readers!
Fern, when you are interested in a robust API documentation platform with extensive language support and strong enterprise partnering.
Mintlify, when you are interested in full-platform artificial intelligence features, with easy-to-swap design templating.
ReadMe, when you are interested in a feature-rich collaboration platform for a non-technical audience, with strong add-on value.
Redocly, when you are interested in a developer-focused API platform, focused on developers as maintainers, with strong enterprise support.
To make reading this section a little more interesting, in addition to providing instructions on how to get started (via quickstart and starter projects), I’m sharing my own experience about what I liked about the process of getting started on each platform, including my favorite parts of each platform’s documentation website.
Additionally, to give you a perspective different from my own, I’ve included anonymized snippets of feedback from information professionals who have used these platforms, excerpted from conversations on the Write the Docs Slack.
Fern has two main products: a static site generator and an SDK generator, and both products integrate with each other. The generator supports TypeScript, Python, GO, Java, C#, PHP, and Ruby. Fern describes itself as a platform that powers both SDK generation and API documentation for a unified developer and agent experience.
How to get started? As described in Fern’s quickstart, clone docs-starter locally, then build and deploy a site with a local server.
What are people saying online?
“Deployments are also SUPER fast -- our old provider took 7-11 minutes to build our site, and Fern doesn't take longer than a minute or two to have changes live. There's also some really robust preview options that don't involve opening a PR and waiting a long time for a build. It's just a great product and we're also amazed with the SDK functionality and are so happy that we can use one provider for docs, API refs, and SDKs.”
How was my experience? This process of spinning up a site only took me a few minutes. One thing I liked during my learning process was that the repository's readme focused on changing parts of the generated site as I was reading the instructions. Trying something yourself and experiencing the change in real-time is always very important when learning something new.
What were my documentation highlights?
Extremely thorough GitHub documentation, particularly in the readme and contributing, RSS support (!) in 2025 on their blog (I do love this), and documentation with a multi-option feedback system that anyone can create a pull request against. (I spent a few minutes looking for typos to fix, but gave up 😞).
Fern
(example site)
Mintlify’s core product is the platform itself. The platform features a web editor, collaboration tools, and writing features, like real-time suggestions and automatic translations. Mintlify describes itself as a platform that focuses on performance and AI-readiness.
How to get started? As described in Mintlify’s quickstart, create an account (so that Mintlify can deploy a unique URL for a starter site). You can also clone a starter project locally.
There are also migration packages for migrating sites to Mintlify.
What are people saying online?
“mintlify is very close to “as code” while providing superior website design.”
How was my experience?
Creating an account and launching an instance of a site was easy. One thing I liked during this process was exploring Mintlify’s dashboard, which contained a multi-tab analytics page, with overview metrics, feedback metrics, and search metrics.
What were my documentation highlights? A technical writing guide maintained from interviews and team insights, themes that made me say out loud, “Wow, these are cool”, and a wall of love that tricked me into reading customer success stories.
Mintlify
(example site)
ReadMe’s core product is the platform itself, which is described as an interactive developer hub for team collaboration. ReadMe describes itself as a platform for the next generation of APIs and has a newer, refactored platform with MDX (JSX) support and bi-directional git sync.
How to get started? As described in the ReadMe quickstart, create an account (so that ReadMe can deploy an instance of what will become your developer hub).
There is also a migration tool for migrating sites built with popular static site generators.
What are people saying online?
“Paying for a tool like ReadMe (which we used to do) saves huge amounts of money because no devs (or tech writers cosplaying as devs) need to keep the infrastructure running. When we elected to build our own infra, we considered Docusaurus, but not for cost reasons. And we went with Vercel's native react framework. All of this costs far more than ReadMe because the dev is expensive.”
How was my experience?
Creating an account and instancing a new project was easy. Similar to my experience with Mintlify, one thing I liked during this process was exploring the ReadMe dashboard, which included collated metrics on API usage (calls, endpoints, errors) and metrics on documentation (views, users, quality, search).
What were my documentation highlights?
Robust changelog detailing the many bugs 🐛 that Owlbert has eaten, community forum support on the website itself, and values-in-action whimsy in their image documentation that highlights a stock image of a man eating a pizza with the caption, “lol he’s eating pizza!”
ReadMe
(example site)
Redocly’s platform is built on top of Redoc, an API documentation generator. Products include Redoc (API reference), Reunite (authoring, collaborating, monitoring), and Realm (container of other products). Redocly describes itself as a platform that helps companies at any level of API maturity win integrations and foster innovation.
How to get started? As described in this Redocly blog post, clone the starter project to build and deploy a site with a local server.
There is also a VS Code extension to write, maintain, and validate OpenAPI documents.
What are people saying online?
“I've used Redocly and they've updated how they price their offerings now to a level that a manager can accept, even for a small company. I'm practically a ride-or-die customer and advocate since 2022. It just works. Engineers take to it very well, too.”
How was my experience?
The process of creating and deploying a site was easy. One thing I liked during this process, similar to my experience with Fern, was following the repository’s readme. I liked learning along the way and even trial-and-erroring a broken lint rule. On the website, it was great that there was a prompt in the UI recommending I switch to a new branch instead of just blinding pushing to main (don’t tell anyone I tried to do that 🤫).
What were my documentation highlights?
A Learning center with modules on OpenAPI, Arazzo, Markdoc, and YAML dedicated to teaching developers instead of leaving them behind, a series of blog posts with consistent sneak peak previews into the team’s roadmap, and a general spirit of “showing, not telling” via instructional visualization across the website and developer hub itself.
Redocly
(example site)
After finishing this article, I looked up the names of every founder and cofounder on GitHub from each of the platforms written above, and … wow, everyone codes a lot. I love that everyone is contributing to open source consistently and that all of these founders are leading by example.
Not that I was going to shame anyone or try to promote undue attention, but I actually could not find a founder from any of these platforms without a seriously impressive commit history for 2025. And some are really impressive. Source: Anonymous GitHub contribution history (2025)
Maybe a vacation is in order 🌴🏖️🏄.