Harper vs Sapling

Harper is a free, open-source grammar checker that flags capitalization, spelling, awkward phrasing, and grammar errors. The maker says checks run locally, with no cloud round-trips, telemetry, or LLM in the loop, and that suggestions appear in under 10 ms. Harper is available through browser and editor extensions, a language server, a JavaScript library, a Rust crate, and native apps. Listed integrations include Chrome, Brave, Edge, Firefox, VS Code, Cursor, Obsidian, WordPress, Neovim, Zed, Helix, Emacs, and Sublime Text. Its language support covers English and British, American, Canadian, Australian, and Indian English dialects. Harper Desktop lets users toggle rules, add dictionary entries, select a dialect, and turn checking on or off per app. The desktop app is labeled beta for macOS 14 or later, and the Windows desktop app is also described as a beta; its binary was not signed at the time of the listed post. Harper is free, with no account or credit card required.

Sapling combines writing assistance for teams with developer tools for adding language model-powered features to applications. Its writing tools include grammar and spelling corrections, autocomplete, rephrasing, tone and sentiment checks, and AI content detection. Style suggestions and tone detection are available, with support for 14 languages. Developers can access HTTP API endpoints and SDK components, including Python and JavaScript client libraries. Sapling lists 73 integration guides, with examples for Zendesk, Salesforce, Slack, Google Docs, Microsoft Word and browser extensions. It is available on the web, through extensions and Windows, via API, and in self-hosted deployments. Sapling says it uses TLS encryption in transit and AES-256 encryption at rest, and describes GDPR compliance and SOC 2 Type II certification. Enterprise accounts include audit logs, role-based access and single sign-on. The free plan has AI detector limits; paid writing assistance starts at $12/user/mo billed annually, and a 30-day trial is listed. API trials have a character limit and expire after one month.