Highlights
Discover what makes Word Koala the smartest vocabulary companion
Instant synonyms
On difficult words — no clicks needed
Simple definitions
Appear inline without breaking your flow
Word difficulty hints
Based on the Zipf frequency scale
Privacy-first
Runs locally, no tracking, no ads
Lightweight
Distraction-free — works on any website
How It Works
Get started in seconds and learn naturally while reading
Install
Install Word Koala from the Chrome Web Store
Browse
Browse any article, blog, or webpage
Hover
Hover over highlighted words to see simpler synonyms
Learn
Learn naturally as you read without breaking focus
💡 You can adjust highlight density and difficulty level in settings
Comparison
See why Word Koala stands out from other extensions
Word Koala
Other Extensions
Privacy
Your data stays yours. Always.
100% Offline Processing
All processing happens locally in your browser. No data ever leaves your device.
Zero Data Collection
No cloud requests, no analytics, no user tracking. Complete privacy guaranteed.
Lightweight & Fast
Zero ads and tracking scripts. Optimized for minimal memory footprint and maximum speed.
Privacy Promise
By installing, you agree that Word Koala only reads visible page text locally for on-device synonym suggestions.
Perfect For
Word Koala helps everyone learn naturally while reading
English Learners
A2–C1 levels
ESL Teachers
Tutors & educators
Book Lovers
Article readers
Writers
Researchers
Everyone
Word lovers
Demo
See Word Koala in action
Live Preview
The ubiquitous smartphone has become paramount to modern life, serving as our primary conduit for communication and information.
Quick Tutorial
Install from Chrome Web Store
Visit any website or PDF
Hover over difficult words
Learn synonyms instantly
FAQ
Frequently asked questions about Word Koala
Does it work everywhere?
Yes — it supports almost every website, including blogs, news, and online readers.
Do I need an account?
No — just install and use instantly.
Is it private?
Absolutely. All processing happens locally in your browser.
Will it slow my pages down?
No — it's built for performance and minimal memory use.
Understand Every Word You Read
Without breaking your flow
By installing, you agree that Word Koala only reads visible page text locally for on-device synonym suggestions.
