ClaudeUsageBar is a free, open-source macOS menu bar app in 2026 that tracks your Claude.ai usage in real-time—showing session (5-hour) and weekly (7-day) percentages, reset countdowns, and smart notifications at 25/50/75/90% thresholds. It pulls data locally via your session cookie from claude.ai (no server involvement), supports Free & Pro plans (including Sonnet weekly for Pro), and stays lightweight (<5MB) with optional Cmd+U shortcut. Privacy-first, no telemetry—ideal for heavy Claude users who hate hitting limits unexpectedly.