Claude Counter
A minimal browser extension that shows token count, cache timer, and usage bars on claude.ai.
Features
- Token count — Approximate token count for the current conversation, with a mini progress bar against the 200k context limit
- Cache timer — Countdown showing how long the conversation remains cached (cheaper to continue)
- Usage bars — Session (5-hour) and weekly (7-day) usage from Claude's native API, with progress bars and reset countdowns (more accurate than the rounded /usage page)
Installation
Chrome / Edge / Chromium
- Download
claude-counter-0.4.2.zip
- Go to
chrome://extensions and enable Developer mode
- Drag and drop the zip onto the page
Firefox
- Download
claude-counter-0.4.2.xpi
- Drag it into any Firefox window and click Add
Userscript
- Install the userscript from
claude-counter.user.js
How it works
- Intercepts Claude's API responses to read conversation data and usage info
- Uses a vendored tokenizer (
o200k_base) for approximate token counting
- Uses Claude’s
/usage plus live SSE message_limit data; the SSE provides exact, unrounded utilization fractions, so the progress bars are more accurate than the rounded percentages shown on Claude’s native /usage page
- Watches for DOM changes to inject UI elements as you navigate
Privacy
- All data stays local — no external servers, no tracking
- Reads your
lastActiveOrg cookie to query Claude's /usage endpoint
- Makes requests only to
claude.ai
Credits
