Now on Chrome & Firefox

Read anything.
Understand everything.

Highlight any word, phrase, or sentence on any webpage. Hilo streams a clear, contextual explanation in seconds — no copy-paste, no tab-switching, no AI wall of text.

5 explanations / day, free · Works on every site

Try Hilo right here.

This paragraph is from a Wikipedia-style article. Highlight the underlined terms with your cursor — like you would on any page.

en.wikipedia.org/wiki/Antikythera_mechanism
highlight a term

Antikythera mechanism

The Antikythera mechanism is an ancient Greek hand-powered orrery — described as the oldest known example of an analogue computer — used to predict astronomical positions and eclipses for calendrical purposes decades in advance. Recovered in 1901 from a shipwreck off the Greek island of Antikythera, its mechanical complexity wasn't matched in Europe for over fourteen hundred years.

Three seconds from confusion to clarity.

Hilo lives quietly in your browser. It only wakes up when you select text, and only sends what's needed.

i

Highlight

Select any word, phrase, or sentence on any page. A small trigger button appears next to your selection.

ii

Click

One click sends only the selection and its surrounding paragraph. Nothing is auto-fired — you stay in control.

iii

Read

The explanation streams in token-by-token, right next to your selection. No new tabs, no pop-ups, no waiting.

Made for the web that's hard to read.

Whenever you'd otherwise open a new tab and Google a term — Hilo is faster.

📰

Articles

Understand any article in your language or switch to translate mode and read Le Monde, Der Spiegel, or Asahi Shimbun.

Technical docs

GitHub READMEs, API references, MCP, documentation, etc. Decode acronyms and terms instantly.

📚

Research papers

ArXiv, PubMed, JSTOR. Get jargon translated in plain English without leaving the abstract.

Free to try. €2 to use it daily.

No credit card to start. Upgrade only if you find yourself reaching the daily limit.

Free
€0 /mo

Perfect for casual reading.

  • 5 explanations per day
  • All three modes (default, simplify, translate)
  • Works on every website
  • Email login, no credit card
Install Hilo

Questions, answered.

What data does Hilo collect?

Only what's required to generate the explanation: the text you selected, the surrounding paragraph for context, and the page title. We never store the text you select or the pages you visit. Full details in our privacy policy.

Which AI model does it use?

Anthropic's Claude. Your selection is sent through our backend (so the API key isn't exposed in the browser) and streamed back token-by-token. We don't keep logs of the text or responses.

Can I use it offline?

No. Explanations are generated by Claude, which requires an internet connection. The extension itself is tiny (~7 KB) but it needs the network to fetch responses.

What languages does it support?

Explanations work in any language Claude supports (50+ including English, French, German, Spanish, Mandarin, Japanese). The extension UI is in English and French today.

How do I cancel Pro?

Cancel any time from the extension's settings page — you keep Pro until the end of your billing period, no questions asked. Payment is handled by Polar.

Can I get a refund?

Yes, you can get a refund within 30 days of your purchase. No questions asked. Please contact me at lucas@hiloapp.dev.

Stop opening tabs. Start understanding.

5 free explanations per day. No card. 30 seconds to install.