CIRCØ is a free, private, browser-based FB2 reader with instant tap-to-translate. Open any FictionBook (.fb2 or .fb2.zip) file, read with a clean paginated interface in dark or light mode, and tap any word — or select a phrase — to translate it immediately without leaving your reading flow. No software install, no account, and your books remain 100% private.
An FB2 translator is a reading tool that allows you to read FictionBook publications in foreign languages and translate vocabulary inline without copy-pasting into external translation tools. CIRCØ parses XML FictionBook structures directly in your browser, converting chapters, footnotes, and illustrations on the fly so you can enjoy immersive language learning.
Why use CIRCØ for FictionBook reading?
Instant word translation: Tap any single word to reveal its meaning, pronunciation, and grammatical context.
Multi-word phrase translation: Long-press or click-and-drag across sentences for full context-aware translations.
Full FB2.ZIP archive support: Directly open compressed .fb2.zip files without needing third-party extraction tools.
Slavic and World literature: Perfect for reading Russian, Ukrainian, and European classics in their original FictionBook formats.
Text-to-speech audio: Listen to authentic pronunciations with integrated neural Kokoro and Edge speech engines.
Private local storage: Your books, reading positions, and highlights are stored exclusively on your device.
Frequently asked questions
What is the difference between FB2 and EPUB?
FB2 (FictionBook) is an open single-file XML format popular for classic literature, whereas EPUB is a packaged zip archive of HTML and CSS. CIRCØ supports both formats seamlessly.
Can I read FB2 books on mobile browsers?
Yes. CIRCØ is designed as a responsive web app. You can read and translate FB2 books on Safari for iOS, Chrome for Android, and all major desktop browsers.
Which translation engines are used?
CIRCØ uses a high-accuracy multi-tier cascade including Google Gemini Flash and on-device offline neural models (Meta NLLB-200), ensuring rapid translation anytime.