Your offline AI for perfect grammar
Effortless AI grammar checking across all your favorite apps. Private, lightning-fast, and always available.
v1.33
macOS 14+
Full-featured 7-day free trial
Writing That Never Leaves Your Mac
Unlike cloud-based tools, Refine processes everything locally using advanced AI models.
Every Word Stays Local
Processed entirely on your device, with nothing uploaded or monitored.
Lightning Fast
Local processing delivers instant results without internet delays.
Always Available
Works offline in flights, coffee shops, or anywhere you write.
Stuck on a Word? Just Write It in Your Language
When you can't think of the right word or phrase, simply write it in your native language. Refine will suggest the perfect translation without interrupting your writing flow.
Inline Suggestions
Get natural phrasing right where you type, without breaking your sentence.
Context-Aware Suggestions
Understands the surrounding context to suggest the most natural translation for each word.
Uninterrupted Flow
Keep writing without stopping to look up words. Just use your native language and continue.
Don't Just Fix It. Understand It.
Refine doesn't just correct your mistakes, it explains them. Click "Explain" and get a clear, AI-powered explanation for any suggestion.
Understand the "Why"
Get explanations for every suggestion to understand the reasoning behind it.
Learn & Grow
Improve your writing skills over time by understanding grammar rules and stylistic choices.
Contextual Insights
Explanations are tailored to your specific text and context, not just generic rules.
Plays Nice with Your Favorite Apps
No setup needed. Just start writing and get instant grammar suggestions.
And many more applications across macOS
Works in Your Language
Grammar checking for 50+ languages and regional dialects.
English
German
French
Spanish
Portuguese
Chinese
Also supports
More Than a Grammar Checker
Everything you need to write clearly and quickly
One Editor for Everything
Send any text to the Floating Editor with a shortcut, then rewrite it with presets like Professional or Concise, translate it, or have it read aloud.
Snippets
Type \ anywhere to pull up your saved snippets, keep typing to filter, and hit return to expand them in place.
Customize with Prompts
Steer each check in your own words.
“Keep informal expressions, colloquialisms, and abbreviated terms unchanged.”
“Use formal language, avoid contractions, and maintain a professional tone.”
Flexible Checking Modes
Choose how and when suggestions appear.
Suggestions appear as you type
Can auto-pause while on battery
Checks only when you press your shortcut
Keyboard Shortcuts
Trigger every action with keys you choose.
Want More Power? Just Bring Your Own Key
While our local models handle most tasks brilliantly, you can connect your own API keys for access to the most advanced AI models.
- Requests go straight to the provider — no proxy, no middleman.
- Keys live in your macOS Keychain, never on our servers.
- Switch between local and cloud models with one click.
Simple, transparent pricing
No monthly subscriptions. No hidden fees. Just a one-time payment for lifetime access.
Lifetime license
Includes all current features and all future updates.
What's included
- 100% private
- Offline grammar checking
- Offline fluency refinement
- Offline rewriting
- Offline AI explanations
- Offline text-to-speech
- Offline translation
- Custom AI prompts
- Customizable appearance
- Works across apps and websites
- Text snippets
- Works in 50+ languages
- Bring your own key
- Use on up to 1 device
- No monthly subscription
- No extra token fees
Lifetime
Pay once, own it forever
Lifetime access for one device
Tax included
30-day money-back guarantee
Secure payment via Stripe
What's New
Latest Updates
Check out the new features and improvements in the latest version.
Version 1.33
Released 6 minutes ago
New Features
- Added an Academic rewrite preset to the Rewrite feature
- Added a chart to writing statistics
- Added support for Afrikaans
Frequently asked questions
Can't find the answer you're looking for? Feel free to send us an email at support@refine.sh
- Is my data truly private?
- Yes, absolutely. Your documents, text, and writing never leave your Mac. We don't collect, store, or transmit any of your personal content. All processing is performed locally using offline generative AI models that run directly on your machine. Once the model is downloaded, Refine works entirely offline. If you'd like, you can even use a firewall app to block its internet connection completely.
- What apps does it work with?
- Works with most macOS apps including Mail, Messages, Safari, Chrome, Pages, Word, Slack, Notion, and many more. For apps that don't support macOS accessibility features (where even VoiceOver can't read the content), you can set up a keyboard shortcut to check your writing with a floating editor without interrupting your work.
- What about system requirements?
- Requires macOS 14.0 or later. For the best experience, at least 16GB of memory is recommended on Apple Silicon Macs (M1, M2, etc.). If you have an Intel Mac or only 8GB of memory, you might want to consider BYOK (Bring Your Own Key) for better performance.
- Is there a free trial?
- We offer a 7-day free trial with full access to all features. No credit card required. Just download the app and start using it.
- What is your refund policy?
- We offer a 30-day no-questions-asked refund policy. If you're not satisfied for any reason, just email us within 30 days of purchase for a full refund.
- Is there an educational discount?
- Yes. We offer a 30% discount for students and educators. Simply enter your edu-issued email on this page and quickly get a discount.
- Do you offer regional pricing?
- Yes. We offer regional pricing based on purchasing power parity (PPP). Regional pricing eligibility is based on the country associated with your IP address.
- What does "lifetime license" mean?
- Your license includes all bug fixes, improvements, and new features. You get full access to the app forever, including all future updates.
- What happens if I register more devices than my license allows?
- Your license allows activation on the number of devices you specified during purchase. If you need more devices, you can upgrade your license limit at any time. If you try to register more devices than your limit, the oldest device will automatically be deactivated to make room for the new one.
- Who is behind Refine?
- I'm an indie developer focused on building small, useful tools that do one thing exceptionally well. I created Refine because I needed a grammar checker that respects privacy and works offline. You might also know my other app, Input Source Pro, which has helped thousands of multilingual users automatically switch input sources. Your support helps me continue improving these tools.
- When will a Windows or Linux version be available?
- Currently, I'm focused on making the macOS version as good as possible. Windows and Linux versions will take some time, and I don't have a timeline yet. If you're interested, you can join the waitlist to be notified when they become available.
Start Refining Your Writing
Download to improve every sentence you write
v1.33
macOS 14+
Full-featured 7-day free trial
