Model tokenizer comparison
GPT-5.6 vs Claude Sonnet 5 Tokens
GPT-5.6 can be explored with its compatible tiktoken encoding, while Claude Sonnet 5 requires Anthropic's model-aware token counting endpoint for an authoritative count.
Accuracy note
This page does not claim a single tokenizer can reproduce both providers. Compare results only after counting the same structured request with each provider's supported method.
Frequently asked questions
Do GPT-5.6 and Claude Sonnet 5 use the same tokenizer?
No. They are separate model families with different token-counting methods.
How can I compare them fairly?
Count the same content and request structure with each provider's supported method, then combine the result with current input, output, and caching prices.