RewriteBar is a macOS AI writing assistant for grammar, rewriting, and translation in any app. Free trial; licenses from $29 one-time.
Researched and fact-checked by Bartu Cavusoglu · Updated October 26, 2026
RewriteBar is a macOS AI writing assistant that improves text in whatever application you are using. You select text, trigger the app with a keyboard shortcut, and choose an action such as fixing grammar, rewriting, summarizing, or translating. The result replaces the original text.
The app is made by Mathias Michel and is built with native macOS tools. The site describes it as lightweight, at roughly 20 to 25 MB depending on the page, and says it runs quietly in the background.
RewriteBar captures the currently selected text through the macOS clipboard and sends it to a language model. The corrected version is pasted back automatically. To do this it asks for macOS Accessibility permissions, which let it read the selection and replace it.
Where the text goes depends on the provider. With the default RewriteBar server, text is forwarded to a model and not stored. With third-party providers such as OpenAI, Mistral, or Ollama, requests go directly from your device to the provider.
The core is a library of predefined actions: Fix Grammar & Spelling, Improve Writing, Simplify Language, Summarize, Make Longer, Title Case, Humanize Text, Extract Action Items, and Create an email. There are also technical actions like Fix JSON Errors and Convert JSON to YAML.
Users can build custom actions, use variables in commands, and chain actions in one flow. A comparison view shows changes line by line or word by word. Translation covers more than 500 languages, and PopClip and keyboard shortcuts provide other ways to trigger actions.
RewriteBar is a macOS AI writing assistant that fixes grammar, rewrites, summarizes, and translates selected text in any app. It captures the selection, sends it to a language model, and pastes the result back.
Standard is a $29 one-time license for one device, and Pro is a $59 one-time license for three devices with a one-year RewriteBar Gateway subscription. Extra devices cost $19 one-time, and RewriteBar Gateway costs $40 per year.
Yes. The Trial plan is free for one device and needs no credit card. The pricing page lists 35,000 one-time credits, while the FAQ mentions up to 100 corrections.
It works with almost any app or website that accepts text input. Examples listed include Google Chrome, Google Docs, Microsoft Word, Slack, WhatsApp, Microsoft Teams, Notion, and Visual Studio Code.
Yes. It supports local models through Ollama, LM Studio, oMLX, Apple Intelligence, and Osaurus. Local models do not add costs, though smaller ones support fewer languages.
The developer states it does not store or track your data. With third-party providers, requests go directly from your device to the provider. With the default RewriteBar server, text is forwarded to a language model and not stored.
No. The site says there is no Windows version and none is planned. A Chrome extension may be explored in the future.
Yes. The site says you can request a refund within 14 days of purchase by emailing the developer.