ClaudeMeter, a new open-source macOS utility dropped on GitHub this week, puts your Claude subscription usage data right in the menu bar where it belongs. Built by developer yotake, the app pulls real-time metrics from Anthropic's private /api/oauth/usage endpoint and displays them as a percentage readout next to the clock - no browser tab required.
How It Works
The app polls Anthropic's API every 5 minutes for subscription usage data, including your current session utilization (tracked on a 5-hour rolling window) and weekly limits broken down by model tier. For Codex CLI users, ClaudeMeter can also parse local log files to display code generation rate limits. The UI respects your macOS system language, supporting both English and Japanese interfaces out of the box.
Authentication Without Keychain Access
ClaudeMeter takes an interesting approach to credential management: instead of touching the macOS Keychain directly (which can trigger antivirus warnings for ad-hoc signed apps), users paste their OAuth token once into the popover. The app stores credentials at ~/Library/Application Support/ClaudeMeter/credentials.json with strict 0600 permissions and handles refresh token rotation automatically. This means after initial setup, you shouldn't need to touch it again - but there's a catch: the first auto-refresh rotates your refresh token, potentially forcing the claude CLI to re-authenticate on its next run.
Tracking Multiple Accounts and API Spend
For power users managing several subscriptions or keys, ClaudeMeter supports multiple accounts that can be switched via the menu bar icon. Optional Admin key integration (sk-ant-admin...) unlocks API spend tracking for the current billing period - useful for teams trying to keep cloud costs from ballooning unexpectedly. Codex rate limit monitoring honors the CODEX_HOME environment variable for custom session directories.
Caveats Worth Knowing
The developer is upfront about the risks: this app relies on a private Anthropic API endpoint and reads local CLI tokens, so an upstream change could break functionality at any time. The released DMG ships ad-hoc signed without notarization, meaning users must manually approve it through System Settings or Terminal after first launch. Rate limiting (HTTP 429) is handled gracefully with exponential backoff using the server's Retry-After header plus a 60-second buffer.
The Bottom Line
ClaudeMeter fills a real gap for Claude Pro and Max subscribers who are tired of navigating to claude.ai just to check if they've burned through their limits. It's a clever hack that proves Anthropic's usage data is accessible - which also means this could be a template for monitoring tooling or even abuse scripts if the API ever gets wider exposure.