1. What TOKENSE is
TOKENSE is a cost-tracking chat client for Anthropic's Claude that runs on your own API key (BYOK). No account, no login, no server-side storage. You can start for well under a cent per message. Operated by Begrit Inc.
2. Getting started (3 steps)
- Generate an API key at console.anthropic.com (free signup, small top-up to start)
- Open TOKENSE and paste the key (stored only on this device)
- Start chatting — cost is measured and optimized automatically
Detailed steps are covered in How to Get an Anthropic API Key.
3. Implemented features
| Feature | What it does |
|---|---|
| Automatic model routing | Routes each question to the right model — cheap models for simple asks, higher-quality models for complex ones |
| Per-message cost display | Shows the real cost of every reply, plus running today/month totals and estimated savings from optimization |
| 166-currency display | Costs are shown automatically in the user's local currency |
| History compression + prompt caching | Automatically summarizes long chat history and leans on caching to keep costs from ballooning |
| Quality audit | Spot-checks answers against a higher-tier model and logs a "quality match rate" |
| PWA support | Works straight from the browser; add to home screen to launch like a native app |
| Bilingual (JA/EN) | Both the app and landing page support Japanese and English |
4. Who it's a good fit for
- Light users of ChatGPT Plus / Claude Pro or Max who feel the flat fee is wasted in quiet months
- Anyone who's hit their Pro/Max usage cap and wants a cheap "overflow" option
- People who want to see the real, itemized cost of their AI usage for budgeting or expensing
- Anyone who wants a single API key instead of paying for multiple separate AI subscriptions
5. Privacy and safety design
It's reasonable to hesitate before handing an API key to a third-party app. TOKENSE stores the key and chat content you paste only in this device's browser (localStorage) and never transmits either to TOKENSE's own servers — in fact, there's no server on TOKENSE's side that stores chats or keys at all.
Network traffic goes to exactly two places:
- Anthropic's Claude API (only your question and its response)
- A once-daily exchange-rate lookup, used solely to display costs in your local currency
The reasoning behind this design is covered in more depth in What Is BYOK?. The habit of checking "where does this app store my key, and where does it send it" is worth applying to any BYOK app, not just TOKENSE.
FAQ
FAQ
- Q. Is TOKENSE really free to use?
- A. Yes, the app itself is free. The only cost you incur is your own Anthropic API usage.
- Q. Does it work on mobile?
- A. Yes — it runs in any browser, and being a PWA, you can add it to your home screen to launch it like a native app.
- Q. Do settings sync across devices?
- A. No. Your API key and chats are stored only in each device's browser, by design, so there's no cross-device sync. You'll need to paste your key on each device you use.
- Q. Who operates TOKENSE?
- A. TOKENSE is operated by Begrit Inc.
- Q. Will a paid plan be added later?
- A. The app itself is free to use as of this writing. Check the official TOKENSE site for any future changes to features or pricing.