MeasureTokensContact

Claude Fable 5 vs GPT-5.1

Same prompt, two tokenizers: see live token counts, cost per request, and token boundaries side by side.

Try:

Counts include each model's own chat-template overhead.

128 chars

Claude Fable 5

Anthropic · 200k context
…tokens

GPT-5.1

OpenAI · 400k context
…tokens

At a glance

  • Claude Fable 5: 200k-token context, $10/1M input · $50/1M output.
  • GPT-5.1: 400k-token context, $1.25/1M input · $10/1M output.
  • Token counts differ between models because each vendor trains its own tokenizer vocabulary — the same text can split into more or fewer pieces. Prices as of 2026-07-07.

Claude Fable 5 token counter →GPT-5.1 token counter →Compare all models →