Token Watcher

by can995835646@gmail.com · Developer Tools

Manifest V3 Free

View in Chrome Web Store Data as of 16 Oct 2026

Real-time MCP call and Token cost monitor for AI developers using Claude, Cursor, and Claude Code.

Users

+2 in 30 days

Rating

0.0 / 5

unchanged in 30 days

Ratings

0 in 30 days

Store rank

#164K

#137K among extensions

Version

1.2.14

updated 16 Jun 2026

Users

monthly, 4 months

Latest, 16 Oct 2026: 16 usersMove the mouse over the chart for any month

Ratings count

monthly, 4 months

Latest, 16 Oct 2026: 0 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About Token Watcher

Track your Claude & ChatGPT token usage in real time. See input/output/cache costs, model breakdown, and MCP call health — right in your browser. Stop guessing what your AI conversations cost. Token Watcher is a lightweight Chrome extension that intercepts Claude.ai and ChatGPT requests to give you real-time visibility into token usage and API costs — no API key required, no external servers. ────────────────────────────── WHAT IT TRACKS ────────────────────────────── ▸ Input tokens, output tokens, cache write & cache read tokens ▸ Per-call cost calculated against current Anthropic and OpenAI pricing ▸ Cumulative daily / weekly costs with a 7-day bar chart ▸ Per-model breakdown — see exactly how much Opus vs Sonnet vs Haiku is costing you ▸ MCP (Model Context Protocol) call health — total calls, error count, error rate ▸ Works on Claude.ai (including the a.claude.ai streaming iframe) and ChatGPT ────────────────────────────── WHY DEVELOPERS LOVE IT ────────────────────────────── ✔ No API key needed — works directly on the Claude.ai and ChatGPT web UIs ✔ Captures exact token counts when available, estimated counts otherwise (marked with ~) ✔ Supports prompt caching metrics (cache_creation_input_tokens / cache_read_input_tokens) ✔ Model-aware pricing — Opus, Sonnet 4/3.7/3.5, Haiku 4.5/3.5/3, GPT-4o, GPT-4, GPT-3.5, o1, o3 ✔ Zero data leaves your browser — everything stored locally via chrome.storage ────────────────────────────── FREE vs PRO ────────────────────────────── FREE: • Real-time token + cost display • 7-day daily trend chart • Per-model breakdown • MCP call health monitoring PRO (via Gumroad license key): • Full 30-day monthly history • CSV export for billing & reporting ────────────────────────────── PRIVACY ────────────────────────────── Token Watcher does NOT: ✗ Send any data to external servers ✗ Require an Anthropic or OpenAI API key ✗ Store conversation content — only token counts and costs All data stays in your browser's local storage. ────────────────────────────── SUPPORTED SITES ────────────────────────────── • claude.ai (all subdomains including a.claude.ai) • chatgpt.com / chat.openai.com