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CIRCØ Extension — Tap-to-Translate for NOOK & Amazon Prime Video

Bring contextual tap-to-translate into the Barnes & Noble NOOK® web reader and Amazon Prime Video. Whether reading foreign-language books on NOOK or watching movies and series on Amazon Prime Video, CIRCØ lets you tap or hover any unfamiliar word or phrase to see a natural, context-aware translation powered by CIRCØ's multi-tier AI translation engine.

Google Chrome

Chrome Web Store

Works with Chrome, Brave, Opera, and other Chromium browsers.

Install from Chrome Web Store

Microsoft Edge

Edge Add-ons

Official certified add-on for Microsoft Edge on Windows and macOS.

Install from Edge Add-ons

Mozilla Firefox

Firefox Add-ons

Supports Firefox Desktop and Firefox for Android tablets and phones.

Install from Firefox Add-ons

How it works

Install the extension from your browser's official store above.
Open the Barnes & Noble NOOK Web Reader or stream any title on Amazon Prime Video.
Tap or click any word in NOOK, or hover and click interactive subtitles on Prime Video. The CIRCØ popover appears directly above the text with an instant translation in sentence context.
Step through word, clause, and full-sentence translation levels with intuitive 1-tap footer controls or secondary clicks, complete with extended context underlining.
Click the bookmark icon on any translated word to save it. When you visit CIRCØ, your saved words sync automatically into your vocabulary review deck.

Key features

Works on NOOK & Amazon Prime Video — tap any word in the NOOK web reader or hover and click interactive subtitles on Amazon Prime Video.
Context-aware translations — translations consider the surrounding sentence so idioms and words with multiple meanings are accurately translated.
Auto-pause & fade subtitles on Prime Video — automatically pauses playback while you inspect a subtitle word, resumes when dismissed, and gently lingers subtitles between dialogue lines so learners have extra time to read.
Expand & collapse controls — step through word, clause, and full-sentence translation levels with intuitive 1-tap footer controls or secondary clicks, complete with extended context underlining.
Visual AI scenes & stock photos — contextual imagery generated to reinforce visual vocabulary acquisition.
Multilingual thesaurus — dual-language synonym lookups with clickable pills to explore alternative expressions in-place.
Audio pronunciation — hear words spoken clearly with natural text-to-speech.
One-click vocabulary deck — save words to your vocabulary list, which automatically synchronizes to your deck on circ0.com.
Smooth reading & viewing experience — custom shadow-DOM popovers and non-intrusive CSS highlights preserve your reading flow on NOOK (without accidental page turns) and your cinema view on Prime Video.
Dark & light theme support — adapts automatically to your browser theme.

Privacy & content safety

CIRCØ is strictly an overlay. It never downloads, copies, or stores your books, full subtitle tracks, or video titles. Only the tapped word/phrase and its surrounding sentence context are sent to circ0.com to perform the requested translation. See our privacy policy for full details.

Supported languages

The extension interface is fully localized in 20 languages (English, Spanish, French, German, Japanese, Chinese Simplified and Traditional, Russian, Portuguese, Italian, Korean, Ukrainian, Polish, Dutch, Turkish, Arabic, Hindi, Swedish, Vietnamese, and Indonesian) and supports translation between 130+ languages.

Try it without an account

You can test the extension without buying a book or signing into Barnes & Noble. Open any free public sample in the NOOK reader — such as the La sombra del viento free sample — and tap any word to experience instant tap-to-translate immediately.

Frequently asked questions

Which browsers and platforms are supported?

CIRCØ Extension is available for Google Chrome, Microsoft Edge, and Mozilla Firefox. It also runs smoothly on other Chromium-based browsers like Brave, Opera, and Vivaldi, as well as Firefox on Android devices, supporting both the Barnes & Noble NOOK web reader and Amazon Prime Video.

Is the extension free?

Yes. The extension is 100% free with no subscriptions, in-app purchases, or usage limits.

Are my books or videos uploaded or stored anywhere?

No. CIRCØ is strictly an overlay. It never downloads, copies, or stores your books, full subtitle tracks, or video titles. Only the tapped word or phrase and its surrounding sentence context are sent to the translation API.

How does subtitle translation work on Amazon Prime Video?

Turn on native subtitles on Amazon Prime Video. CIRCØ renders interactive subtitle tokens that automatically pause playback while you inspect a word, resume when dismissed, and gently linger dialogue between lines so learners have extra time to read.

Does tapping a word in NOOK turn the page accidentally?

No. Word taps are intercepted by the extension to show the translation popover without triggering NOOK page navigation. Tapping outside the popover in empty whitespace turns pages normally.

How do saved words sync to CIRCØ?

When you visit circ0.com in the same browser, your saved words automatically merge into your reading history and vocabulary deck so you can review words anytime.

Support & feedback

Questions or suggestions? Visit circ0.com or reach out to circ0@circ0.com. See our privacy policy and terms of use.

Explore CIRCØ Web Reader →

Questions? Email circ0@circ0.com. See our privacy policy and terms of use.