Anthropic: Claude Fable 5.1 vs OpenAI: GPT-5.5 Pro
Anthropic: Claude Fable 5.1 is 3× cheaper for input tokens: Anthropic: Claude Fable 5.1 costs $10.00 per M and OpenAI: GPT-5.5 Pro costs $30.00 per M. Anthropic: Claude Fable 5.1 is 3.6× cheaper for output tokens: Anthropic: Claude Fable 5.1 costs $50.00 per M and OpenAI: GPT-5.5 Pro costs $180.00 per M. About the same: Anthropic: Claude Fable 5.1 takes up to 1,000,000 tokens of context and OpenAI: GPT-5.5 Pro up to 1,050,000.
| Anthropic: Claude Fable 5.1 | OpenAI: GPT-5.5 Pro | |
|---|---|---|
| Model id | anthropic/claude-fable-5.1 | openai/gpt-5.5-pro |
| Input | $10.00 per M | $30.00 per M |
| Output | $50.00 per M | $180.00 per M |
| Context length | 1,000,000 tokens | 1,050,000 tokens |
| Accepts | file, image, text | file, image, text |
| Produces | text | text |
| Served by | anthropic | openai |
Prices are the providers' list prices per million tokens, as of . Both run on your own provider key through one OpenAI-compatible endpoint, with no fee on the tokens.