head to head · open source
Zen Browser vs Harper
Zen Browser has 44,481 GitHub stars, 1,754 forks, 689 open issues and last shipped yesterday. Harper has 15,469 stars, 632 forks, 896 open issues and last shipped yesterday. Zen Browser leads on adoption by 188% (44,481 vs 15,469 stars). Zen Browser is written in C++ under MPL-2.0; Harper is written in Rust under Apache-2.0. Zen Browser has attracted 4% as many forks as stars, Harper 4%. Zen Browser was the more recently maintained of the two, and both are self-hostable with no licence fee.
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
| Zen Browser | Harper | |
|---|---|---|
| GitHub stars | ★ 44K | ★ 15K |
| License | MPL-2.0 | Apache-2.0 |
| Written in | C++ | Rust |
| Last push | 2026-09-17 | 2026-09-17 |
| Forks | ⑂ 1.8K | ⑂ 632 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Zen Browser if
- You weight community size — 44K stars and counting
- You want the MPL-2.0 license terms
- Your stack matches C++
- You value the larger contributor base for long-term maintenance
pick Harper if
- You want the Harper feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Rust
- You evaluated both and Harper fits your workflow better
About Zen Browser
Zen Browser is a privacy focused, open source web browser built on Firefox’s Gecko engine. It inherits Firefox’s compatibility and extension ecosystem while introducing a streamlined interface and productivity oriented features. The project lives in the desktop browser ecosystem, targeting users who want a Firefox based experience with reduced clutter and enhanced customization.
read the full Zen Browser overview →
About Harper
Harper is offline, privacy first grammar checker for English. It lives in productivity, browser extension, developer tools, and text editing ecosystem. Project is open source under Apache 2.0. GitHub metadata shows 15373 stars, 627 forks, and 896 open issues. Last push is 2026 09 14. Category is Productivity & Utilities / Browsers & Extensions. It uses Rust for core, WebAssembly for browser loading, language server for editors, JavaScript package for web and Node.js apps. It solves slow, costly, network dependent grammar checking. It replaces Grammarly and LanguageTool as named in README. Grammarly sends writing …
read the full Harper overview →
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Frequently asked questions
Is Zen Browser or Harper more popular?
Zen Browser has 44,481 GitHub stars and Harper has 15,469. Zen Browser has the larger community by that measure.
Are Zen Browser and Harper free?
Both are open source. Zen Browser is licensed under MPL-2.0 and Harper under Apache-2.0. Neither carries a licence fee.
What is the difference between Zen Browser and Harper?
Zen Browser is written in C++ and Harper in Rust. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Zen Browser or Harper?
Choose Zen Browser if you want the larger community (44,481 stars) or its MPL-2.0 licence terms. Choose Harper if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.