About Harper
Editor integrations include VS Code, Neovim, Zed, Emacs, Sublime, and Obsidian, while browser and desktop coverage includes Chrome and Firefox extensions plus a macOS desktop app and a WordPress block-editor plugin.
All checks execute locally with no cloud round-trips or telemetry, preserving user text privacy and enabling inline suggestions without server delays.Harper supports multiple English dialects (US, UK, Canadian, Australian, Indian) and offers programming-language-aware checks via editor integrations.
The project is available under the Apache‑2.0 license on GitHub with documentation, rule reference, and contribution guides for customization and extension.
Key Features
- Real-time grammar, spelling, capitalization, and phrasing suggestions
- Runs on-device; all checks execute locally with no cloud round-trips or telemetry
- Provides a language server and developer libraries (harper-ls, harper.js, harper-core, Rust crate) for integration
- Editor, browser, and desktop integrations (VS Code, Neovim, Zed, Emacs, Sublime, Obsidian; Chrome/Firefox extensions; macOS app; WordPress plugin)
- Open-source (Apache-2.0) on GitHub with documentation, rule reference, and contribution guides for customization and extension
Use Cases
- Integrate Harper via its language-server and developer libraries into your team's IDEs and editors to get real-time, code-aware grammar, spelling and phrasing suggestions in pull requests and commits while preserving privacy with local-only checks and support for multiple English dialects
- Embed Harper on privacy-sensitive devices and apps to provide on-device grammar, capitalization and style corrections for writers, journalists and legal teams without sending text to the cloud, leveraging the open-source library for easy customization
- Add Harper to your publishing and CI workflows to automatically enforce dialect-specific style guides and perform automated proofreading before release, using editor integrations and on-device checks to keep content private and reproducible
Who is it for?
- Software developers
- Programmers
- Technical writers
- Content creators
- Open-source contributors
Based on 9 verified user reviews — Average rating: 3.67/5
@randyallen2294
TurkeyHafif işler için idare eder. Muhteşem değil ama basit işleri çıkarıyor.
@ambersmith2428
TurkeyI have been using Harper for a few weeks on real client work, not just demos. The first week was mostly learning prompts and figuring out which templates stick. After that, drafting time dropped noticeably — especially for outlines, email replies, and first-pass summaries. It is not flawless: long documents sometimes lose structure, and I still fact-check anything important. Still, for a busy week it has become one of the tools I open without thinking. If you already have a clear workflow, Harper fits in cleanly. If you expect magic with zero editing, you will be disappointed. For me, the time saved on the boring middle steps is worth it.
@esperverett9389
TurkeyHarper ilk geçişler için işime yarıyor. Mükemmel değil ama faydalı.
@ralphmiller7375
TurkeyMixed results with Harper. Good on short tasks, weaker on longer ones.
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