Model Comparison
Claude Fable 5 vs GPT-5.5 ProWhich is better in 2026?
Claude Fable 5 significantly outperforms across most benchmarks. Claude Fable 5 is 3.4x cheaper per token.
Verdict: Claude Fable 5 vs GPT-5.5 Pro — which is better?
Claude Fable 5 (by Anthropic) and GPT-5.5 Pro (by OpenAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.
Claude Fable 5 outperforms in 1 benchmarks (Humanity's Last Exam), while GPT-5.5 Pro is better at 0 benchmarks. Claude Fable 5 significantly outperforms across most benchmarks.
On price, Claude Fable 5 is roughly 3.4x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.5 Pro also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Choose Claude Fable 5 if…
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
- cost matters — it's about 3.4x cheaper per token
- you want the most recent training data — it shipped Jun 2026
Choose GPT-5.5 Pro if…
- you process long inputs — it offers a 1,050,000 token context window
Performance Benchmarks
Comparative analysis across standard metrics
Claude Fable 5 outperforms in 1 benchmarks (Humanity's Last Exam), while GPT-5.5 Pro is better at 0 benchmarks.
Claude Fable 5 significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Fable 5 ($10.00/1M tokens) is 3.0x cheaper than GPT-5.5 Pro ($30.00/1M tokens).
For output processing, Claude Fable 5 ($50.00/1M tokens) is 3.6x cheaper than GPT-5.5 Pro ($180.00/1M tokens).
In conclusion, GPT-5.5 Pro is more expensive than Claude Fable 5.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.5 Pro accepts 1,050,000 input tokens compared to Claude Fable 5's 1,000,000 tokens. Both models can generate responses up to 128,000 tokens.
Input Capabilities
Supported data types and modalities
Both Claude Fable 5 and GPT-5.5 Pro support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Fable 5
GPT-5.5 Pro
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Claude Fable 5 was released on 2026-06-09, while GPT-5.5 Pro was released on 2026-04-23.
Claude Fable 5 is 2 months newer than GPT-5.5 Pro.
Jun 9, 2026
1 months ago
1mo newerApr 23, 2026
2 months ago
Knowledge Cutoff
When training data ends
GPT-5.5 Pro has a documented knowledge cutoff of 2025-12-01, while Claude Fable 5's cutoff date is not specified.
We can confirm GPT-5.5 Pro's training data extends to 2025-12-01, but cannot make a direct comparison without Claude Fable 5's cutoff date.
—
Dec 2025
Provider Availability
Claude Fable 5 is available from Anthropic. GPT-5.5 Pro is available from OpenAI.
Claude Fable 5
GPT-5.5 Pro
Outputs Comparison
Key Takeaways
Claude Fable 5
View detailsAnthropic
GPT-5.5 Pro
View detailsOpenAI
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against Claude Fable 5 and GPT-5.5 Pro side-by-side, then vote on the output you prefer.
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FAQ
Common questions about Claude Fable 5 vs GPT-5.5 Pro.