head to head · open source
Bruno vs OpenAPI-Specification
Bruno has 47,982 GitHub stars, 3,066 forks, 1,831 open issues and last shipped 2 days ago. OpenAPI-Specification has 31,291 stars, 9,146 forks, 80 open issues and last shipped 12 days ago. Bruno leads on adoption by 53% (47,982 vs 31,291 stars). Bruno is written in JavaScript under MIT; OpenAPI-Specification is written in Markdown under Apache-2.0. Bruno has attracted 6% as many forks as stars, OpenAPI-Specification 29%. Bruno was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 1 topic tag (openapi), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Bruno | OpenAPI-Specification | |
|---|---|---|
| GitHub stars | ★ 48K | ★ 31K |
| License | MIT | Apache-2.0 |
| Written in | JavaScript | Markdown |
| Last push | 2026-11-01 | 2026-10-22 |
| Forks | ⑂ 3.1K | ⑂ 9.1K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Bruno if
- You weight community size — 48K stars and counting
- You want the MIT license terms
- Your stack matches JavaScript
- You value the larger contributor base for long-term maintenance
pick OpenAPI-Specification if
- You want the OpenAPI-Specification feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Markdown
- You evaluated both and OpenAPI-Specification fits your workflow better
About Bruno
Bruno Opensource IDE for exploring and testing APIs. English Українська Русский Türkçe Deutsch Français Português (BR) 한국어 বাংলা Español Italiano Română Polski 简体中文 正體中文 العربية 日本語 ქართული Nederlands فارسی Bruno is a new and innovative API client, aimed at revolutionizing the status quo represented by Postman and similar tools out there. Bruno stores your collections directly in a folder on your filesystem. We use a plain text markup language, Bru, to save information about API requests. You can use Git or any version control of your choice to collaborate over your API collections. Bruno is offline only. There…
read the full Bruno overview →
About OpenAPI-Specification
The OpenAPI Specification The OpenAPI Specification is a community driven open specification within the OpenAPI Initiative, a Linux Foundation Collaborative Project. The OpenAPI Specification (OAS) defines a standard, programming language agnostic interface description for HTTP APIs. This allows both humans and computers to discover and understand the capabilities of a service without requiring access to source code, additional documentation, or inspection of network traffic. When properly defined via OpenAPI, a consumer can understand and interact with the remote service with a minimal amount of implementation…
read the full OpenAPI-Specification overview →
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Frequently asked questions
Is Bruno or OpenAPI-Specification more popular?
Bruno has 47,982 GitHub stars and OpenAPI-Specification has 31,291. Bruno has the larger community by that measure.
Are Bruno and OpenAPI-Specification free?
Both are open source. Bruno is licensed under MIT and OpenAPI-Specification under Apache-2.0. Neither carries a licence fee.
What is the difference between Bruno and OpenAPI-Specification?
Bruno is written in JavaScript and OpenAPI-Specification in Markdown. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Bruno or OpenAPI-Specification?
Choose Bruno if you want the larger community (47,982 stars) or its MIT licence terms. Choose OpenAPI-Specification if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.