It builds up over time
Every word you look up and every passage you work through is saved. Next time you meet it, the answer is already there.
A reading companion for macOS
Stuck on a
sentence?
In any app on your Mac, select a passage and press ⌘⌥E — explain, translate, or rewrite it on the spot. What you look up stays with you.
Download trial
macOS trial · 32MB · pick your AI model on first launch · Apple silicon
First time? Read the guide →
Three lines, that is the whole thing
It stays on your machine
The AI runs locally — nothing is uploaded. No account, no cloud, works offline.
Always one shortcut away
Word, your browser, a PDF, a chat window — just select. Not happy with a result? Keep talking to it, or say what you want out loud.
Once you select, here is what it does
Explain
A word, a concept, or a whole paragraph you cannot parse — explained in plain language.
Translate
Translate between languages, reading the surrounding text you did not select. The same word lands differently depending on whether the passage is about finance or a hobby.
Rewrite & polish
Official notices, emails, posts — made clearer and on-tone, following the voice of the whole passage rather than standing out.
Capture from screen
Text in a scanned PDF, an image, or a video that you cannot select — capture it, and explain, translate, or rewrite all the same.
It learns your range
It recalls what you looked up even when phrased differently, and over time speaks to the fields and level you tend to read at.
Save it
A key point from a book, a line worth keeping, a thread to research — select or capture it into your collection. When enough has piled up, “Export” lets the AI sort it, summarize each part, and hand you a tidy document.
Start free, go further, bring your own
The built-in on-device model handles everyday reading at no cost, with nothing uploaded. For sharper explanations or more natural translations, connect your own cloud key.
- Download once, use forever
- Fully offline — text never leaves your Mac
- No account, no cloud, works offline
- Good enough for daily use
- Deeper explanations, more natural translations, better-tuned rewrites
- Bring your own key (Doubao / DeepSeek / ChatGPT / Gemini…)
- Pay per use, on your own account
- One setting; each action picks its own engine
Three steps, that is all
- 1
Select the text
In any app, highlight the passage you want to understand or improve.
- 2
Press ⌘⌥E
A small window appears right next to the text — no need to switch apps.
- 3
Explain / translate / rewrite
The result arrives at once. Everything you look up is saved, ready in the menu bar.
Installation
Notarized by Apple — opens cleanly.
- 1Double-click the downloaded DMG file.
- 2Drag the Jinnang icon into your Applications folder.
- 3Open it. If macOS asks whether to open an app downloaded from the internet, click Open.
- 4Follow the in-app prompt to grant Accessibility permission, so it can read the text you select.
Everything runs locally. What goes into Jinnang stays on your own machine.