🦀📊 Claude Usage Limit Tracker

A Chrome extension that monitors your Claude.ai usage limits and saves them to a local JSON file — useful for scripting, dashboards, or just keeping an eye on how close you are to your limits.

What it does

Park a tab on https://claude.ai/settings/usage. Whenever the page fetches updated usage data (on load and roughly every 10 minutes), the extension:

• Saves the raw API response to ~/Downloads/claude-usage-{org-id}.json
• Shows a small overlay in the top-right corner of the page with your current utilisation and a linear extrapolation of where you'll be by the time each window resets

The overlay looks like this:

              🦀📊 Claude Usage Limit Tracker
                             JSON downloaded
                                2 minutes ago
                     5h: 65% (108% by 4pm)
                      7d: 18% (27% by 4th)

Clicking JSON in the overlay reveals the file in Finder.

The extrapolated percentages can exceed 100% — that's intentional. It means you're on track to hit your limit before the window resets.

Install

1. Clone or download this repo
2. Open Chrome and go to chrome://extensions/
3. Enable Developer mode (toggle in the top-right)
4. Click Load unpacked and select the repo folder

Use

1. Open a tab and navigate to https://claude.ai/settings/usage
2. Keep the tab open — the extension will keep it alive even when backgrounded
3. Watch ~/Downloads/claude-usage-{org-id}.json for updates

The JSON file contains your raw usage data from the Claude API:

{
  "five_hour": {
    "utilization": 65,
    "resets_at": "2026-03-28T16:00:00+00:00"
  },
  "seven_day": {
    "utilization": 18,
    "resets_at": "2026-04-04T02:00:00+00:00"
  },
  ...
}

Permissions used

Permission	Why
downloads	Save the JSON file to ~/Downloads/
downloads.ui	Suppress the download bubble for silent saves
tabs	Prevent the parked tab from being discarded by Chrome
host_permissions: https://claude.ai/*	Intercept the usage API response

No data is sent anywhere. Everything stays on your machine.