HappyTokenizer
HappyTokenizer is a browser-based token analysis tool designed for developers, prompt engineers, and AI product teams. It enables users to inspect token boundaries, compare model encodings, and estimate API spend before deploying prompts to production. The application runs entirely client-side to ensure prompt text remains private on the user machine. It supports real-time analysis across multiple vendors and model families, helping optimize context windows and control tokenization costs.
Checked on Nov 2, 2026.
Alternative resources
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