Obsidian
Check your notes in Obsidian with inline highlights and explanations.
A grammar checker that stays on your Mac
- Fully private
- Works offline
- Checks as you type
- Context-aware AI
- 36 languages
- Native Mac app
Every fix comes with a reason
Plain-language reasons, one click away.
The rule behind the fix
Every suggestion shows the rule it's based on, so you're never guessing what changed.
Grounded in your sentence
Explanations point at the words you actually wrote, not a generic textbook rule.
Mistakes you stop repeating
Seeing the rule once is how it sticks. Over time, you reach for Explain less.
Made to fit how you write
Rewriting, snippets, and your own rules.
The reason for the delay is due to the fact that we are currently in the process of reviewing the proposal.
21 words107 characters
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.
My address is \
address
123 Maple Street
email
alex@example.com
sig
Best regards, Alex
Snippets
Type \ anywhere, filter as you type, and press return to expand a snippet in place.
Custom prompts
Steer each check in your own words.
Grammar checks
Keep informal expressions, colloquialisms, and abbreviated terms unchanged.
Fluency checks
Use formal language, avoid contractions, and maintain a professional tone.
Checking modes
Choose how and when suggestions appear.
Automatic
Suggestions appear as you type
Can auto-pause while on battery
Manual
Checks only when you press your shortcut
Keyboard shortcuts
Trigger every action with keys you choose.
Apply suggestionTab
Dismiss suggestionEsc
Open Floating Editor⌘4
Check in English (British)⌘⇧E
Bring your own key
Connect your own API key when you want more powerful models.
- Requests go straight to the provider. No proxy, no middleman.
- Keys live in your macOS Keychain, never on our servers.
- Each task runs on the model you pick.
Grammar checksLocal Model
Fluency checksLocal Model
ExplanationsGPT-5
TranslationClaude Sonnet
RewriteGemini
Works with your favorite apps
Get grammar suggestions right where you write.
Messages
Chrome
Slack
Bear
Obsidian
Day One
Telegram
Outlook
Zen
Orion
CotEditor
Todoist
OneNote
eM Client
Mail
Pages
Notion
Ulysses
Craft
Spark
WhatsApp
Arc
Brave
TextEdit
Typora
Fantastical
Teams
Linear
Safari
Word
Notes
Discord
Scrivener
Firefox
iA Writer
Dia
Edge
BBEdit
Things
Evernote
Signal
Reminders
Refine inside your other tools
Plugins connect to Refine on your Mac. With local models, your text stays on your Mac.
Want to connect another tool? Build your own integration with the open Refine Protocol.
Get the plugin
Neovim
Grammar and fluency suggestions in your Neovim buffer.
PopClip
Select text in any app and check it with Refine.
Start free. Pay when it earns a place in your writing.
No subscription. No hidden fees.
Compare Refine with other grammar checkersFree
$0/try it first
No account, no credit card
- Core grammar checking
- Limited advanced features
- Occasional reminders
- Upgrade anytime
Lifetime
$38USD/lifetime
Your writing never leaves your Mac.
- All features unlocked
- All future updates
- Use on 1 device
- No monthly subscription
- No extra token fees
30-day money-back guarantee
Recent releases
- Expanded shortcut options for applying and dismissing suggestions, including combinations like Option + →, double-tapping Command, or pressing both Option keys together.
- Improved compatibility across apps, with more reliable suggestion highlighting and application
- Improved compatibility with macOS 27
- Added Lithuanian grammar checking and rewriting
+3 more in this release
- Improved performance when writing replies to long email threads in Apple Mail
+2 more in this release
Frequently asked questions
Didn't find your answer? Email support@refine.sh.
- Is my data truly private?
- With a local model selected, Refine processes your writing on your Mac. If you use a cloud AI service with your own API key, Refine sends text directly to that service for the tasks you assign to it. The service's privacy policy applies. For offline checks, download a local model and select it for each task you use, such as grammar checking or rewriting. If you choose to report a suggestion, Refine receives the original and revised text included in your report.
- What apps does it work with?
- Most Mac apps, including Mail, Messages, Safari, Chrome, Pages, Word, Slack, and Notion. A few apps don't expose their text through macOS accessibility, so even VoiceOver can't read them. For those, a keyboard shortcut sends your text to the Floating Editor.
- What about system requirements?
- macOS 14 or later. An Apple Silicon Mac with 16GB of memory runs the local model comfortably. On an Intel Mac or with 8GB, the local model will be slow, so use your own API key instead.
- Is Refine free?
- Yes. Refine is free to download and use. No account, no credit card. The free version covers core grammar checking, with occasional reminders and limited access to the advanced features. A one-time license unlocks everything, forever.
- What is your refund policy?
- Email support@refine.sh within 30 days of purchase for a full refund, no questions asked.
- Is there an educational discount?
- Yes, 30% off for students and educators. Submit your school email on this page and a discount code arrives by email within 24 hours.
- Do you offer regional pricing?
- Yes. Prices are adjusted by purchasing power parity. If your country qualifies, the offer shows up in the pricing section automatically.
- Can I get an invoice with my company and VAT details?
- Yes. After purchase, open your license page and choose Create invoice next to the purchase, then add your legal business name, billing address, and an optional VAT or business tax ID. Enter the details carefully: the finished Stripe invoice cannot be edited, and each purchase can have only one.
- What does "lifetime license" mean?
- You pay once. Every future version, including new features, is included.
- What happens if I register more devices than my license allows?
- You can view and deactivate your devices on the license page. If you've reached your device limit, deactivate a device you no longer use before activating a new one.
- Can I activate Refine offline?
- Yes. Refine supports Offline Activation. When you start activation in Refine, follow the in-app instructions: you'll need another device that can access the internet, such as a phone, to scan the QR code, confirm the device, download an Offline License File, then move that file back to your Mac and import it in Refine. An offline-activated device uses one device slot and cannot be deactivated for the first 30 days after activation. After that, you can release the slot from your license page.
- Who is behind Refine?
- I'm Runju Huang, an indie developer. I built Refine because I wanted a grammar checker that works offline and doesn't read my writing. You might know my other app, Input Source Pro, which switches input sources automatically for thousands of multilingual users. License sales are what fund the work.
- When will a Windows or Linux version be available?
- Not soon. I'm focused on the Mac version and don't have a timeline for Windows or Linux. Join the waitlist and I'll email you when there is one.
Say exactly what you mean. Keep every word yours.
Checks with a local model run on your Mac. If you choose a cloud AI service, your text goes directly to that service.
Download for Mac
brew install --cask refinev1.39macOS 14+Free, no account
- Private and offline by default
- Grammar and fluency checks
- Explanations for every fix
- Rewrite, translate, read aloud
- Snippets that expand anywhere
- Custom prompts for each check
- 36 languages, 59 varieties
- Works in the Mac apps you use
- Obsidian, Neovim, PopClip plugins
- Bring your own API key