CapMeter

Know your Claude or Codex limit before you hit it

Developer ToolsLaunched Sep 2026

The story

CapMeter is a macOS menu bar app that watches how fast you're burning through your Claude or Codex usage and turns it into a time estimate -- "limit in ~1h 18m" -- instead of just a percentage. It tracks both providers side by side, sends threshold alerts to Slack, Discord or any webhook, keeps exportable history, and includes a floating widget that stays above every window and Space. Everything runs locally: no backend, no analytics, no tracking. Free for 14 days, then a single one-time purchase, no subscription.

Overview

CapMeter reads your own logged-in Claude.ai or Codex/ChatGPT session and shows how much of your usage window is left as a live percentage in the macOS menu bar. Instead of stopping there, it estimates a time until you'll hit the limit based on how fast you're burning through it, so you can plan a task instead of getting cut off mid-way. It's aimed at developers and heavy AI-tool users who run Claude Code, Codex CLI, or long chat sessions and want to see the risk coming rather than discover it. Everything runs on-device: no backend, no analytics, no account with the developer.

Key features

Burn-rate time estimate

Turns your usage percentage into a countdown -- "limit in ~1h 18m" -- instead of a bare number.

Claude and Codex, side by side

Tracks both providers independently in one popup, switchable without opening a browser.

Alerts to Slack, Discord, or any webhook

Threshold notifications reach you where you already are, with quiet hours so they don't fire at night.

Floating widget

Stays visible above every window and full-screen app, across every Space.

Use cases

1
Claude Code / Codex CLI power users
Running long agent sessions and want to know before a task gets cut off mid-way by the session limit.
2
People juggling both Claude and Codex accounts
Tired of switching between two menu bar apps or browser tabs to see two separate usage numbers.

FAQ

Do I have to give it my Anthropic or OpenAI password?

No. You sign in on Claude's or OpenAI's own page inside the app, the same page you'd normally use. CapMeter never sees your password -- it only keeps the session that sign-in produces, encrypted with the macOS Keychain.