Claude Fable 5 vs GPT-5.5 Pro

Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.

Claude Fable 5

Anthropic · Jun 2026

The first GA model of Anthropic's Mythos class — a tier above Opus — and the current SWE-bench Verified leader, at $10/$50 per 1M tokens.

GPT-5.5 Pro

OpenAI · Apr 2026

The maximum-compute tier of GPT-5.5 for the hardest research, math and engineering problems, at a steep per-token premium.

The verdict

These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: Claude Fable 5 works out roughly 3.4x cheaper per blended million tokens.

Specs & pricing

Claude Fable 5GPT-5.5 Pro
modhub Index
Input price / 1M$10$30
Output price / 1M$50$180
Context window1M1M
Max output128K128K
Open weightsnono
Reasoning modelyesyes
Multimodal inputtext, imagetext, image
Knowledge cutoffJan 2026Jan 2026
ReleasedJun 2026Apr 2026
Example monthly cost*$175.00$570.00

* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.

Frequently asked questions

Which is better, Claude Fable 5 or GPT-5.5 Pro?
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: Claude Fable 5 works out roughly 3.4x cheaper per blended million tokens.
Which is cheaper, Claude Fable 5 or GPT-5.5 Pro?
Claude Fable 5 costs $10/$50 per million input/output tokens, while GPT-5.5 Pro costs $30/$180. For a typical workload of 10M input and 1.5M output tokens per month, that's $175.00 versus $570.00.
Which model is better for coding, Claude Fable 5 or GPT-5.5 Pro?
We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.

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