User guide
OnlyTranslate primarily supports Chrome. The extension also includes a complete searchable guide that works offline; this page covers the information most useful before installation.
Installation
Install OnlyTranslate from the Chrome Web Store, then pin the extension to your browser toolbar.
You can also download a release package from GitHub Releases and install it manually.
Translate your first webpage
- Open a regular webpage you want to translate.
- Select the OnlyTranslate icon in the browser toolbar.
- Choose an available translation service.
- For your first translation, try Bilingual and Smart.
- Select Translate current page.
To restore the page, open the extension again and select Restore original.
Smart or Full page
Smart
Best for articles, blogs, posts, comments, and long-form reading. It prioritizes the main reading area and reduces noise from menus, navigation, subscription buttons, and sidebar recommendations.
Full page
Best for documentation, admin pages, forums, tool sites, and information-dense pages. It translates more visible text and also serves as a fallback when Smart misses content.
Video subtitles
OnlyTranslate can read an existing subtitle track on supported websites, translate it in context-aware segments, and show bilingual subtitles that follow playback.
The main supported platforms are:
- YouTube;
- Udemy;
- Coursera;
- Khan Academy.
The video must already provide a subtitle track that OnlyTranslate can read. OnlyTranslate does not currently include speech recognition and cannot generate subtitles for a video without them.
EPUB and PDF (Beta)
Open Reading and library (Beta) from the bottom of the extension popup and select Import book to import a local DRM-free EPUB or PDF. When you open an accessible online PDF, you can also choose Read this PDF with OnlyTranslate and then add it to your library from the reader.
The EPUB reader supports chapter translation, a table of contents, bookmarks, themes, font controls, and line spacing. The PDF reader supports page-based bilingual reading, translation-only and original-layout translation views, reading progress, adding to the library, and exporting the original file.
PDF uses basic layout analysis without an extra download by default. For multi-column, chart-heavy, or otherwise complex pages, you can explicitly download the optional local layout model of about 23 MB from the PDF reader's More menu. It stays in extension-private storage, can be removed at any time, and automatically falls back to basic analysis if download or processing fails.
The current beta supports local DRM-free EPUB and PDF files plus accessible online PDFs. It does not support MOBI, DRM- or password-protected books, cloud sync, notes, or AI content analysis. Reading position is saved automatically; before uninstalling, use the full library to back up original files, progress, and bookmarks.
Translation services
No-setup services such as Microsoft Translator and Google Translate work immediately. OpenAI, DeepSeek, Gemini, Claude, DeepL, and similar services require an API key under their respective terms.
Some providers may charge or apply usage limits. Those rules are set by the provider.
Frequently asked questions
Why can’t extension-store and browser-internal pages be translated?
Chrome does not allow ordinary extensions to run on the extension store, browser settings, and some security-restricted pages.
Why did Smart miss part of the page?
Smart prioritizes the main reading area. Scroll until dynamically loaded content appears and translate again, or switch to Full page.
Is my data uploaded?
Settings, cache, library, and reading progress stay in your browser. When you use an online translation service, the text being translated is sent to the provider you selected. See the privacy notice for details.
How do I report a problem?
Open a GitHub issue and, when possible, include:
- the affected page URL;
- the translation scope and display mode;
- the selected translation service;
- steps to reproduce the problem;
- a screenshot or error message without private information.