lexiSelect a word. The translation, definition and pronunciation appear next to it.
lexi is a small app for Mac and Windows made for Chinese-speaking international students and people who recently moved abroad. Select text in a PDF, Word document, browser or notes app, press ⌥ ` on Mac or Ctrl Alt T on Windows, and a small window shows the translation, dictionary definitions, pinyin for Chinese characters and a read-aloud button. Then it quietly gets out of the way.
What it does
- Translates the selection offline. 50 languages, as listed in the offline model catalogue, detected automatically or pinned; the target language is yours to choose, including from Chinese into other languages. Each language pair downloads once on first use (English to French is about 62 MB) and then works without a connection. On Mac you can switch to Apple's translation engine. Offline quality varies by language pair.
- Works in any app. The shortcut works wherever text can be selected. On Mac, the window can also appear right after you select in common reading apps (Preview, Word, Chrome, Safari, Edge, Firefox, PDF Expert, Adobe Reader, Obsidian, Typora, TextEdit); on Windows, turn on "translate after selecting" in settings.
- Dictionary definitions. From the macOS system dictionary on Mac, and on both platforms one-click links to Oxford and Cambridge English-Chinese, an optional community dictionary, and optional Oxford API access with your own key.
- Pinyin for Chinese characters. Select a character or word and see its Mandarin reading, with alternatives for characters that have several. Traditional characters are converted first.
- Pronunciation. System voices read the original or the translation aloud, US or UK English.
- Slang and context. Built-in notes for common internet slang, plus an optional AI explanation using your own Chat Completions-compatible endpoint, sent only when you click.
Who it is for
Students reading papers and textbooks who can follow the argument but get stuck on a term. Newcomers dealing with leases, bank letters and government websites. Heritage learners and partners who need the reading of a Chinese character. lexi is not designed to translate whole pages; browser page translation does that better.
Privacy
Translation happens on your computer. The first time you use a language pair, lexi downloads its model files and sends none of your text. No translation history is stored, there is no account and no analytics. The optional Oxford, community-dictionary and AI features send only the current selection, only when you enable them and click. Details are on the privacy page (Chinese).
Price
Free for 14 days with no limits, then 5 free lookups per day. A one-time payment of US$4.99 unlocks lexi permanently, including future updates, on all your own Macs and Windows PCs with the same key. No subscription. Payment is handled by Stripe; the license key is shown immediately after checkout and verified offline. Full refund within 14 days of purchase.
Requirements and install
Mac: macOS 15 or later on Apple Silicon. The app is not notarized by Apple, so on first launch you allow it once under System Settings › Privacy & Security, then grant Accessibility permission so it can read the selected text. Windows: Windows 10 or 11, 64-bit; the installer is not code-signed, so SmartScreen may ask you to choose "More info" and "Run anyway". The step-by-step install guide is in Chinese.