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Model Comparison

Claude Fable 5 vs GPT-5.4Which is better in 2026?

Claude Fable 5 significantly outperforms across most benchmarks. GPT-5.4 is 3.6x cheaper per token.

Verdict: Claude Fable 5 vs GPT-5.4 — which is better?

Claude Fable 5 (by Anthropic) and GPT-5.4 (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 6 benchmarks (DeepSWE 1.1, FrontierSWE, Humanity's Last Exam, Legal Agent Benchmark, OSWorld-Verified, SWE-Bench Pro), while GPT-5.4 is better at 1 benchmark (LiveBench). Claude Fable 5 significantly outperforms across most benchmarks.

On price, GPT-5.4 is roughly 3.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Choose Claude Fable 5 if…

  • you want the strongest raw capability — it leads on 6 of 7 shared benchmarks
  • you want the most recent training data — it shipped Jun 2026

Choose GPT-5.4 if…

  • cost matters — it's about 3.6x cheaper per token

Performance Benchmarks

Comparative analysis across standard metrics

7 benchmarks

Claude Fable 5 outperforms in 6 benchmarks (DeepSWE 1.1, FrontierSWE, Humanity's Last Exam, Legal Agent Benchmark, OSWorld-Verified, SWE-Bench Pro), while GPT-5.4 is better at 1 benchmark (LiveBench).

Claude Fable 5 significantly outperforms across most benchmarks.

Fri Aug 07 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-5.4 costs less

For input processing, Claude Fable 5 ($10.00/1M tokens) is 4.0x more expensive than GPT-5.4 ($2.50/1M tokens).

For output processing, Claude Fable 5 ($50.00/1M tokens) is 3.3x more expensive than GPT-5.4 ($15.00/1M tokens).

In conclusion, Claude Fable 5 is more expensive than GPT-5.4.*

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

Lowest available price from all providers
Fri Aug 07 2026 • llm-stats.com
Anthropic
Claude Fable 5
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
OpenAI
GPT-5.4
Input tokens$2.50
Output tokens$15.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Both models have the same input context window of 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-5.4
Input1,000,000 tokens
Output128,000 tokens
Fri Aug 07 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Fable 5 and GPT-5.4 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-5.4

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-5.4

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Fable 5 was released on 2026-06-09, while GPT-5.4 was released on 2026-03-05.

Claude Fable 5 is 3 months newer than GPT-5.4.

Claude Fable 5

Jun 9, 2026

1 months ago

3mo newer
GPT-5.4

Mar 5, 2026

5 months ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

Claude Fable 5 is available from Anthropic. GPT-5.4 is available from OpenAI.

Claude Fable 5

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

GPT-5.4

openai logo
OpenAI
Input Price:Input: $2.50/1MOutput Price:Output: $15.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Higher DeepSWE 1.1 score (70.0% vs 52.0%)
Higher FrontierSWE score (90.0% vs 54.0%)
Higher Humanity's Last Exam score (64.5% vs 39.8%)
Higher Legal Agent Benchmark score (13.3% vs 0.4%)
Higher OSWorld-Verified score (85.0% vs 75.0%)
Higher SWE-Bench Pro score (80.0% vs 57.7%)
OpenAI
Less expensive input tokens
Less expensive output tokens
Higher LiveBench score (80.3% vs 78.3%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Fable 5 and GPT-5.4 side-by-side, then vote on the output you prefer.

Claude Fable 5
✓ Preferred
GPT-5.4
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Fable 5
OpenAI
GPT-5.4

FAQ

Common questions about Claude Fable 5 vs GPT-5.4.

Which is better, Claude Fable 5 or GPT-5.4?

Claude Fable 5 significantly outperforms across most benchmarks. Claude Fable 5 is made by Anthropic and GPT-5.4 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-5.4 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-5.4 scores Tau2 Telecom: 98.9%, ARC-AGI: 93.7%, Graphwalks BFS <128k: 93.0%, GPQA: 92.8%, Graphwalks parents <128k: 89.8%.

Is Claude Fable 5 cheaper than GPT-5.4?

GPT-5.4 is 4.0x cheaper for input tokens. Claude Fable 5 costs $10.00/M input and $50.00/M output via anthropic. GPT-5.4 costs $2.50/M input and $15.00/M output via openai.

What are the context window sizes for Claude Fable 5 and GPT-5.4?

Claude Fable 5 supports 1.0M tokens and GPT-5.4 supports 1.0M 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-5.4?

Key differences include input pricing ($10.00 vs $2.50/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Fable 5 and GPT-5.4?

Claude Fable 5 is developed by Anthropic and GPT-5.4 is developed by OpenAI.

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