Select anything, right-click, get an instant AI explanation in context. On-device — no account, no cloud, free.
Users
7
+2 in 30 days
Rating
0.0 / 5
unchanged in 30 days
Ratings
0
0 in 30 days
Store rank
#224K
#188K among extensions
Version
0.1.0
updated 24 Jun 2026
Users
monthly, 4 months
Latest, 20 Oct 2026:7 usersMove the mouse over the chart for any month
Ratings count
monthly, 4 months
Latest, 20 Oct 2026:0 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About Whatsit — What's this?
Select any word, right-click, and instantly understand it — explained in the context of what you're actually reading. 100% on-device AI. Free.
The same word means different things in different places. Whatsit reads the
surrounding paragraph, so:
• "Apple" in a recipe → the fruit
• "Apple" in tech news → the company
• "Stockholm" in a travel guide → the city
• "Stockholm" in market news → the stock exchange
• "transformer" in an AI paper → the neural network architecture
HOW IT WORKS
1. Select a word or phrase on any page
2. Right-click → "What's this?"
3. The answer streams into a small card right at your selection
PRIVATE BY ARCHITECTURE
Whatsit runs entirely on YOUR device using Chrome's built-in AI
(Gemini Nano). It makes zero network requests. No account, no cloud,
no tracking, no history kept. What you read stays on your machine —
not as a policy promise, but because there is no server to send it to.
GREAT FOR
• Reading news, papers, or documentation full of unfamiliar terms
• Reading in your second language — definitions that fit the sentence,
not dictionary guesswork
• Anyone who's tired of opening a new tab to Google every odd word
REQUIREMENTS
Chrome 138+ with on-device AI support (~22 GB free disk and a modern
GPU, or 16 GB RAM). The first lookup downloads the model once.
Explanations are generated in English.
Free. No signup. Select, right-click, understand.