Youdao Browser Extension Complete Guide

The Youdao Translate browser extension is an essential tool for anyone who regularly reads foreign-language web content. Once installed, simply highlight any word, phrase, or paragraph on a webpage and the translation appears instantly in a popup — no window switching, no copy-pasting required. Beyond basic hover-to-translate functionality, the extension also supports full page translation, PDF translation, and input translation, making it the perfect companion for reading foreign websites, handling international emails, and browsing global news.

The Youdao browser extension currently supports Chrome (and all Chromium-based browsers including Edge, Brave, Arc, and Opera), Firefox, and Safari. The extension is remarkably lightweight at approximately 2MB and consumes minimal system resources, ensuring your browser's performance remains unaffected. The 2026 edition integrates Youdao's Ziyue large language model translation engine, delivering more accurate and natural hover-translate results than ever before. Let's walk through installation and usage in detail.

Installation Guide

Installation varies slightly across browsers, but the overall process is quick and straightforward.

Chrome / Edge Installation

Firefox Installation

In Firefox, visit the official Firefox Add-ons store, search for "Youdao Translate," and click "Add to Firefox." Confirm the permissions prompt and the extension will be installed immediately. We recommend pinning it to your toolbar for easy access. The Firefox version offers identical functionality to the Chrome version, ensuring a consistent experience across browsers.

Core Features Explained

Hover-to-Translate (Selection Translation)

Hover-to-translate is the extension's flagship feature and by far the most frequently used. Simply select any word, phrase, or text passage on any webpage, and the translation result appears in a floating popup near the selected text. The popup displays comprehensive results including: basic definitions, phonetic pronunciation (with clickable American/British English audio), word forms, common collocations, and example sentences. For individual word lookups, the extension pulls from Youdao's authoritative dictionary databases (including Collins English-Chinese Dictionary), providing exceptionally detailed entries.

The hover-to-translate feature supports three trigger modes: Auto-translate on selection (popup appears automatically when text is highlighted), Double-click translate (double-click a word to trigger), and Key-triggered translate (hold Ctrl/Alt while selecting text). You can choose your preferred trigger mode in the extension settings to avoid unwanted popups when translation isn't needed. This flexibility ensures the extension adapts to your workflow rather than interrupting it.

Full Page Translation

When you need to read an entire foreign-language webpage, hover-to-translate becomes inefficient. That's where full page translation comes in. Click the Youdao icon in your toolbar and select "Translate this page" — the entire webpage's text content will be translated into your target language while preserving the original page layout and formatting. Full page translation offers two display modes: "Translation only" and "Bilingual comparison." The bilingual mode displays original and translated text in parallel, making it excellent for reading comprehension and language learning. Page translation typically completes within 2-3 seconds for standard web pages.

PDF Translation

The Youdao browser extension can directly translate PDF files opened in your browser. After opening a PDF, click the extension icon and select "Translate PDF." The system automatically recognizes text content within the PDF and provides translations as an overlay that preserves the original formatting. This feature is incredibly valuable for reading foreign-language academic papers, technical documentation, and reports online without needing to download files and upload them to a separate translation tool. It supports PDFs up to 50 pages for free users and unlimited pages for VIP subscribers.

Input Translation

Clicking the Youdao icon in your toolbar opens an input box where you can type or paste text for translation. This supports multiple language pairs including Chinese-English, Chinese-Japanese, Chinese-Korean, and many more. Input translation is perfect for quickly checking phrases while composing foreign-language emails or messages, or for translating text that's difficult to select with hover-to-translate (such as text within images or interactive elements).

Advanced Settings & Configuration

Custom Keyboard Shortcuts

In the extension settings page, you can customize keyboard shortcuts for various actions. For example, bind full page translation to Alt+T, toggle hover-to-translate with Ctrl+Shift+Y, or set up a quick shortcut for input translation. Custom shortcuts dramatically improve efficiency, especially for power users who translate frequently throughout the day.

Blacklist & Whitelist

If you don't want hover-to-translate active on certain websites (such as your native-language sites or company intranet), add those domains to the blacklist. Conversely, if you only want translation enabled on specific sites, use whitelist mode. Both modes are easily configurable in the extension settings. You can also quickly toggle the extension on/off for the current site via the toolbar icon without modifying your lists.

Translation Engine Selection

The extension allows switching between the standard NMT translation engine and the Ziyue LLM translation engine. The LLM engine produces higher-quality translations, particularly for long sentences and context-dependent content, but adds approximately 0.3 seconds of latency. The standard engine is faster and more responsive, ideal for quick browsing. We recommend using the LLM engine for careful reading and the standard engine for casual browsing.

Frequently Asked Questions