Model Comparison

Claude Fable 5 vs GPT-5.5Which is better in 2026?

Claude Fable 5 significantly outperforms across most benchmarks. GPT-5.5 is 1.8x cheaper per token.

Verdict: Claude Fable 5 vs GPT-5.5 — which is better?

Claude Fable 5 (by Anthropic) and GPT-5.5 (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 7 benchmarks (Finance Agent v2, FrontierSWE, GDPval-AA, Humanity's Last Exam, Legal Agent Benchmark, OSWorld-Verified, SWE-Bench Pro), while GPT-5.5 is better at 1 benchmark (LiveBench). Claude Fable 5 significantly outperforms across most benchmarks.

On price, GPT-5.5 is roughly 1.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5.5 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 7 of 8 shared benchmarks
  • you want the most recent training data — it shipped Jun 2026

Choose GPT-5.5 if…

  • cost matters — it's about 1.8x cheaper per token
  • you process long inputs — it offers a 1,050,000 token context window

Performance Benchmarks

Comparative analysis across standard metrics

8 benchmarks

Claude Fable 5 outperforms in 7 benchmarks (Finance Agent v2, FrontierSWE, GDPval-AA, Humanity's Last Exam, Legal Agent Benchmark, OSWorld-Verified, SWE-Bench Pro), while GPT-5.5 is better at 1 benchmark (LiveBench).

Claude Fable 5 significantly outperforms across most benchmarks.

Fri Jul 17 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-5.5 costs less

For input processing, Claude Fable 5 ($10.00/1M tokens) is 2.0x more expensive than GPT-5.5 ($5.00/1M tokens).

For output processing, Claude Fable 5 ($50.00/1M tokens) is 1.7x more expensive than GPT-5.5 ($30.00/1M tokens).

In conclusion, Claude Fable 5 is more expensive than GPT-5.5.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Jul 17 2026 • llm-stats.com
Anthropic
Claude Fable 5
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
OpenAI
GPT-5.5
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5.5 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.

Anthropic
Claude Fable 5
Input1,000,000 tokens
Output128,000 tokens
OpenAI
GPT-5.5
Input1,050,000 tokens
Output128,000 tokens
Fri Jul 17 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Fable 5 and GPT-5.5 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Fable 5

Text
Images
Audio
Video

GPT-5.5

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Fable 5

Proprietary

Closed source

GPT-5.5

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Fable 5 was released on 2026-06-09, while GPT-5.5 was released on 2026-04-23.

Claude Fable 5 is 2 months newer than GPT-5.5.

Claude Fable 5

Jun 9, 2026

1 months ago

1mo newer
GPT-5.5

Apr 23, 2026

2 months ago

Knowledge Cutoff

When training data ends

GPT-5.5 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's training data extends to 2025-12-01, but cannot make a direct comparison without Claude Fable 5's cutoff date.

Claude Fable 5

—

GPT-5.5

Dec 2025

Provider Availability

Claude Fable 5 is available from Anthropic. GPT-5.5 is available from OpenAI.

Claude Fable 5

anthropic logo
Anthropic
Input Price:Input: $10.00/1MOutput Price:Output: $50.00/1M

GPT-5.5

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

Anthropic
Higher Finance Agent v2 score (56.3% vs 51.8%)
Higher FrontierSWE score (90.0% vs 73.0%)
Higher GDPval-AA score (60.5% vs 37.8%)
Higher Humanity's Last Exam score (64.5% vs 52.2%)
Higher Legal Agent Benchmark score (13.3% vs 2.1%)
Higher OSWorld-Verified score (85.0% vs 78.7%)
Higher SWE-Bench Pro score (80.0% vs 58.6%)
OpenAI
Larger context window (1,050,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher LiveBench score (80.7% vs 78.3%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Fable 5 and GPT-5.5 side-by-side, then vote on the output you prefer.

Claude Fable 5
✓ Preferred
GPT-5.5
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Fable 5
OpenAI
GPT-5.5

FAQ

Common questions about Claude Fable 5 vs GPT-5.5.

Which is better, Claude Fable 5 or GPT-5.5?

Claude Fable 5 significantly outperforms across most benchmarks. Claude Fable 5 is made by Anthropic and GPT-5.5 is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Fable 5 compare to GPT-5.5 in benchmarks?

Claude Fable 5 scores SWE-Bench Verified: 95.0%, FrontierSWE: 90.0%, OSWorld-Verified: 85.0%, Terminal-Bench 2.1: 84.3%, SWE-Bench Pro: 80.0%. GPT-5.5 scores Tau2 Telecom: 98.0%, ARC-AGI: 95.0%, GPQA: 93.6%, ARC-AGI v2: 85.0%, GDPval-MM: 84.9%.

Is Claude Fable 5 cheaper than GPT-5.5?

GPT-5.5 is 2.0x cheaper for input tokens. Claude Fable 5 costs $10.00/M input and $50.00/M output via anthropic. GPT-5.5 costs $5.00/M input and $30.00/M output via openai.

What are the context window sizes for Claude Fable 5 and GPT-5.5?

Claude Fable 5 supports 1.0M tokens and GPT-5.5 supports 1.1M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Fable 5 and GPT-5.5?

Key differences include context window (1.0M vs 1.1M), input pricing ($10.00 vs $5.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Fable 5 and GPT-5.5?

Claude Fable 5 is developed by Anthropic and GPT-5.5 is developed by OpenAI.

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