AI-Powered Vocabulary

Learn languages while browsing the web

Highlight unknown words, translate instantly, and build your vocabulary while reading websites and PDFs or watching YouTube

Install Free Extension See how it works

Step 1

Read what you love

Read websites and PDFs or watch YouTube in your target language. The extension works everywhere. Over 50 languages supported.

Step 2

Discover & save new words

Click any word or phrase to translate and save it in one tap. Spotlight mode reveals your knowledge gaps.

Step 3

Remember forever

Smart flashcards and AI trainer turn saved words into lasting knowledge.

See exactly which words you don't know

Spotlight mode shows which words are new for you directly on the page. Instantly understand what you know and what you need to learn.

https://wordbyword.io

Nuances révélées par chaque mot

Apprendre des mots étrangers, c'est élargir délibérément son horizon intérieur. Chaque terme nouvellement acquis révèle une perspective insoupçonnée et transforme subtilement notre manière de percevoir le monde. À mesure que le lexique s'enrichit, la pensée gagne en justesse et en clairvoyance, en discernement, ouvrant la voie à une compréhension plus profonde et plus nuancée de la réalité qui nous entoure. Cette quête perpétuelle de savoir enrichit l' esprit...

Spotlight mode

63%

You understand
this page

Build your personal vocabulary

A smart system that grows with you as you read

Collections

Organize vocabulary from real content. Every article, video, or PDF becomes a source of new words grouped into collections.

Word status

Track learning progress for every word. From unknown to mastered — see how your vocabulary grows across all content.

Public collections

Learn from curated vocabulary lists created by the community. Start with ready-made sets for any topic or level.

Questions?

Is WordByWord free?

Yes. The core features — translations, vocabulary tracking, and flashcards — are completely free. A Premium plan unlocks unlimited collections, AI-powered exercises, and enhanced voiceover.

How do I get started?

Install the Chrome extension, sign in with your Google account — it takes just a few seconds. Then open any website and start highlighting words to translate and save them.

Does it work with YouTube?

Yes! WordByWord integrates with YouTube subtitles. You can hover over words in subtitles to translate them, save to collections, and the video auto-pauses so you don't miss anything.

What languages are supported?

WordByWord supports 50+ languages including English, Spanish, French, German, Japanese, Chinese, Korean, and many more. You can learn multiple languages at the same time.

Is my data safe?

Yes. We store your vocabulary and learning progress to power the app. For full details, see our Privacy Policy. We never sell your data to third parties.

Does it slow down my browser?

No. The extension activates only when you interact with it. It processes content efficiently and has no noticeable impact on page load times or browsing speed.

Can I import and export my words?

Yes! You can import words from CSV files and export your collections to CSV or PDF — so your vocabulary is always portable.

Can I share my collections?

Yes! You can make any collection public so others can learn from your word sets. Browse community collections to find ready-made vocabulary for any topic.