# Harper

> Offline English grammar checking — An English grammar checker that runs on your own machine, so what you write never leaves it.

- Page: https://tesign.com/en/item/harper/
- JSON: https://tesign.com/en/item/harper/index.json
- Korean Markdown: https://tesign.com/item/harper/index.md
- Generated: 2026-09-18 21:08 UTC

## Numbers

- 15,443 stars — checked on GitHub 2026-09-17 03:25 UTC (+4 observed since the check)
- 7-day +14 observed via GH Archive (as of 2026-09-18 15:00 UTC)
- 24h +4 ★ · 30d +18 ★ (as of 2026-09-18 15:00 UTC)
- Star total = the value last checked on GitHub (stars_checked_at) + increases observed via GH Archive since. The 24h · 7d · 30d gains are GH Archive hourly events summed to the reference time (as_of). No score of ours.

## AT A GLANCE

- LICENSE: Apache-2.0 (permissive) — https://spdx.org/licenses/Apache-2.0.html
- USAGE: Commercial use, redistribution OK. Keep notices; mark changes.
- OPEN SOURCE: YES
- LANGUAGE: Rust
- PLATFORM: web
- CATEGORY: PRODUCTIVITY
- Tags: 영문 교정 · 문법 · 오프라인 · 프라이버시
- How to start: Use in the browser
- SOURCES: GitHub https://github.com/automattic/harper
- TRY: https://writewithharper.com/

## ACTIVITY

- Last commit: 2026-09-16 21:20 UTC
- Latest release: [unconfirmed]
- Contributors: [unconfirmed]
- Open issues (incl. PRs): [unconfirmed]
- Made by: [unconfirmed]
- Checked on GitHub: 2026-09-17 03:25 UTC

## TESIGN TAKE

A practical alternative if you write English email or docs often but do not want another subscription. Its suggestions are restrained enough not to flatten your own voice.

## WHY IT MATTERS

The author spells out the reasoning in the README: existing checkers were expensive and overbearing, and everything you wrote was sent to their servers. The main alternative needed gigabytes of RAM. Harper runs locally, so there is no network round-trip while you revise.

## BUILD FROM THIS

- Written in Rust under the Apache-2.0 licence. Because the checking happens locally, it works without a network connection.

## WHO IT'S FOR

- Anyone writing English email, proposals or documentation, especially where drafts must not be sent to an outside server.

## START IN 5 MINUTES

```
# Paste a sentence at writewithharper.com to see the checks first, then follow the site's guide to connect it to your editor.
```

## CAVEATS

- English only — it does not check Korean spelling or grammar.

## RECEIPT

- FIRST SEEN BY TESIGN: 2026-09-17 01:24 UTC
- AT SOURCE: 2023-10-22 02:58 UTC
- KEPT: 2026-09-18 21:07 UTC
- Published on TESIGN: 2026-09-18 21:07 UTC
- Text last updated: 2026-09-18 21:07 UTC

## How to read this

- This file was produced by the same build, from the same data, as the tesign.com item page. The text is editorial; the numbers are stored observations.
- null in the JSON means not observed — never zero. The Markdown writes [unconfirmed] for it.
- Star total = the value last checked on GitHub (stars_checked_at) + increases observed via GH Archive since. The 24h · 7d · 30d gains are GH Archive hourly events summed to the reference time (as_of). No score of ours.
- A summary, not legal advice.

[Image] https://tesign.com/img/harper-5400f1ade3.png