Overview
Developer-first platform for building APIs. Define your API once in Fern's simple format and generate SDKs, documentation, and server boilerplate. Supports OpenAPI import. Acquired by Postman in January 2026 and continues as a standalone product.
When you want a unified approach to SDKs and documentation, prefer code-first over spec-first, or need server code generation alongside client SDKs.
Details
Languages & Runtimes
Categories
Spec Support
Best For
Code-first API tooling that generates SDKs, docs, and server code from a simple definition
Related tools
View all in SDK Generator →README badges
If your tool is listed on devxtools.dev, you can add a badge to your README or docs that links to your listing. It's optional, it's free, and nobody will chase you about it.
What the badge means
The badge says your tool is listed in the devxtools.dev catalog and that we've reviewed the listing against official sources, with a dated check. That's all it means.
It doesn't mean that we endorse or recommend the tool over alternatives, that anyone paid for the listing (nobody can), or that the tool won a comparison.
[](https://devxtools.dev/tools/fern/)<a href="https://devxtools.dev/tools/fern/"><img src="https://devxtools.dev/badge/fern.svg" alt="Listed on devxtools.dev" height="20"></a>Usage rules
- Only for listed tools. Use the badge only if your tool has a live listing at the URL it links to.
- Link to your listing. Keep the link pointing at your devxtools.dev listing page, not the home page or somewhere else.
- Don't modify it. Don't change the badge's wording, colours or logo.
- It's optional, and it has no effect. Adding the badge, or not adding it, doesn't affect your listing, its position, or any comparison or verdict.