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Preview of Mira Translator - Web Translation

Mira Translator - Web Translation by David Bai

Web translation, YouTube bilingual subtitles, AI translation & vocabulary

Available on Firefox for Android™Available on Firefox for Android™
4 (4 reviews)4 (4 reviews)
72 Users72 Users
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About this extension
Immersive Web Translation · YouTube Bilingual Subtitles · AI Translation · Word Lookup · Vocabulary

Mira Translator is a privacy-focused browser extension designed for web translation and language learning. It supports immersive web translation, YouTube bilingual subtitles, AI-powered translation, word lookup, vocabulary building, terminology management, input box translation, quick translation windows, and custom translation settings for different websites.

› Free Basic Translation
  Works immediately after installation, with no account registration or API Key setup required.
  • Immersive bilingual web translation
  • YouTube bilingual subtitles
  • Built-in Google and Bing translation
  • Support for desktop browsers and selected Android browsers

› AI Translation
  Use your own API Key to connect with various AI and translation services:
  GPT · Gemini · Claude · DeepL · Groq · SiliconFlow · Ollama and more
  Supports custom API endpoints for other compatible AI services.
  AI translation understands context and surrounding content to reduce unnatural literal translations.
  Your API Key is stored locally. AI translation requests are sent directly to the service you choose.

› Terminology Management
  Create custom terms and preferred translations.
  Useful for technical documents, learning materials, and professional content where consistent terminology matters.
  Terms added to the terminology list can be automatically highlighted on webpages.

› Website-Specific Translation Settings
  Works together with global settings to create website allowlists or blocklists.
  Each website can have its own translation preferences:
  • Enable or disable automatic translation
  • Enable or disable word lookup translation
  • Choose which parts of a webpage should be translated
  Use the smart selector to quickly choose specific webpage elements for translation.
  Website settings are saved automatically and can be synced across devices.
  Supports popular websites such as Facebook, Instagram, X, Reddit, and GitHub.

› Smart Translation Cache
  Stores translation results separately for different translation engines to reduce repeated requests and improve speed.
  Frequently used translations can reuse existing results, reducing unnecessary AI translation calls.
  AI translation results can also be reused by traditional machine translation engines (NMT) to improve consistency and reduce duplicate translations.
  Unused cache data can be cleaned automatically to keep the extension running smoothly.

› Hover Translation Shortcut
  Hover over paragraphs or words and use a shortcut key to translate instantly, without selecting or copying text.

› Input Box Translation
  Translate text directly inside any webpage input field.
  No need to switch pages or copy and paste. Quickly convert your messages into another language for smoother communication with people around the world.

› Quick Translation Window
  Open a translation window instantly on any website with a keyboard shortcut.
  Translate text without leaving the current page, ideal for quick lookups, conversations, and everyday translation needs.

› YouTube Bilingual Subtitles
  Enable the video's built-in CC subtitles to use this feature.
  • Bilingual subtitle display
  • Real-time subtitle preview
  • Subtitle download
  • Look up and save words directly from subtitles

› YouTube/X Video Speech Recognition
  Use AI speech recognition to generate video subtitles and translate them.
  Useful for YouTube or X (Twitter) videos without available subtitles.

› AI Image Translation
  Send webpage images to AI services for image understanding and translation.
  Useful for screenshots and image-based content containing text.

› Word Lookup and Vocabulary
  Double-click a word to look it up and save it to your vocabulary list.
  Saved words can be automatically highlighted on webpages and YouTube subtitles, making it easier to review while reading or watching videos.

› Cross-Device Sync
  Supports WebDAV, Google Drive, and OneDrive synchronization.
  Sync vocabulary, terminology, and related settings between desktop browsers and supported Android browsers such as Firefox and Edge.

› Privacy Protection
  Mira Translator does not collect your browsing content.
  Your API Key is stored locally, and AI translation requests are sent directly to the service you select without passing through third-party proxy servers.

› Lightweight and Fast
  Built with native JavaScript and requires no additional background service.
  Designed to provide a fast, flexible, and customizable translation experience.

Free · Private · Customizable · Feature-Rich
Rated 4 by 4 reviewers
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
3.5.8.640
Size
427.03 KB
Last updated
a day ago (Sep 28, 2026)
Related Categories
  • Language Support
License
All Rights Reserved
Version History
  • See all versions
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