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Claude Fable 5.1 vs GPT-5 mini

Claude Fable 5.1 leads the LLM Stats Score 55.9 to 27.3. GPT-5 mini is 29.1x cheaper per token.

Anthropic · OpenAI · Updated for 2026

Which is better?

Claude Fable 5.1 leads the overall LLM Stats Score 55.9 to 27.3, ranking #2 overall.

In the 1 individual benchmarks reported for both models, Claude Fable 5.1 wins 1; this is a narrower head-to-head signal than the composite indexes.

On price, GPT-5 mini is roughly 29.1x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Fable 5.1 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Fable 5.1

  • overall performance matters — it scores 55.9 and ranks #2 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results
  • you process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose GPT-5 mini

  • cost matters — it's about 29.1x cheaper per token

At a glance

The differences that matter most.

Core performance indexes
55.9
#2
27.3
#143
53.0
#5
26.6
#143
Cost, coverage & limits
Benchmark wins
1 of 1
0 of 1
Input price
$10.00 / M
$0.25 / M
Output price
$50.00 / M
$2.00 / M
Context window
1,000,000
400,000

Individual benchmarks

7 reported for Claude Fable 5.1 · 5 for GPT-5 mini

1 shared

Claude Fable 5.1 outperforms in 1 benchmarks (Humanity's Last Exam), while GPT-5 mini is better at 0 benchmarks.

Claude Fable 5.1 significantly outperforms across most benchmarks.

Sun Sep 13 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

GPT-5 mini costs less

For input processing, Claude Fable 5.1 ($10.00/1M tokens) is 40.0x more expensive than GPT-5 mini ($0.25/1M tokens).

For output processing, Claude Fable 5.1 ($50.00/1M tokens) is 25.0x more expensive than GPT-5 mini ($2.00/1M tokens).

In conclusion, Claude Fable 5.1 is more expensive than GPT-5 mini.*

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

Lowest available price from all providers
Sun Sep 13 2026 • llm-stats.com
Anthropic
Claude Fable 5.1
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
OpenAI
GPT-5 mini
Input tokens$0.25
Output tokens$2.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

Claude Fable 5.1 accepts 1,000,000 input tokens compared to GPT-5 mini's 400,000 tokens. Both models can generate responses up to 128,000 tokens.

Anthropic
Claude Fable 5.1
Input1,000,000 tokens
Output128,000 tokens
OpenAI
GPT-5 mini
Input400,000 tokens
Output128,000 tokens
Sun Sep 13 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Fable 5.1 and GPT-5 mini support multimodal inputs.

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

Claude Fable 5.1

Text
Images
Audio
Video

GPT-5 mini

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 5.1

Proprietary

Closed source

GPT-5 mini

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Fable 5.1 was released on 2026-09-01, while GPT-5 mini was released on 2025-08-07.

Claude Fable 5.1 is 13 months newer than GPT-5 mini.

Claude Fable 5.1

Sep 1, 2026

1 weeks ago

1.1yr newer
GPT-5 mini

Aug 7, 2025

1.1 years ago

Knowledge Cutoff

When training data ends

GPT-5 mini has a documented knowledge cutoff of 2024-05-30, while Claude Fable 5.1's cutoff date is not specified.

We can confirm GPT-5 mini's training data extends to 2024-05-30, but cannot make a direct comparison without Claude Fable 5.1's cutoff date.

Claude Fable 5.1

GPT-5 mini

May 2024

Provider Availability

Claude Fable 5.1 is available from Anthropic. GPT-5 mini is available from OpenAI.

Claude Fable 5.1

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

GPT-5 mini

openai logo
OpenAI
Input Price:Input: $0.25/1MOutput Price:Output: $2.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Claude Fable 5.1 and GPT-5 mini side-by-side, then vote on the output you prefer.

Claude Fable 5.1
✓ Preferred
GPT-5 mini
Open in Playground

FAQ

Common questions about Claude Fable 5.1 vs GPT-5 mini.

Which is better, Claude Fable 5.1 or GPT-5 mini?

Claude Fable 5.1 leads the LLM Stats Score 55.9 to 27.3. Claude Fable 5.1 is made by Anthropic and GPT-5 mini is made by OpenAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Fable 5.1 compare to GPT-5 mini in benchmarks?

Claude Fable 5.1 scores OSWorld 2.0: 77.9%, CursorBench v3.2: 73.4%, Humanity's Last Exam: 65.0%, GDPval-AA: 61.8%, Terminal-Bench 4.0: 55.8%. GPT-5 mini scores AIME 2025: 91.1%, HMMT 2025: 87.8%, GPQA: 82.3%, FrontierMath: 22.1%, Humanity's Last Exam: 16.7%.

Is Claude Fable 5.1 cheaper than GPT-5 mini?

GPT-5 mini is 40.0x cheaper for input tokens. Claude Fable 5.1 costs $10.00/M input and $50.00/M output via anthropic. GPT-5 mini costs $0.25/M input and $2.00/M output via openai.

What are the context window sizes for Claude Fable 5.1 and GPT-5 mini?

Claude Fable 5.1 supports 1.0M tokens and GPT-5 mini supports 400K 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 5.1 and GPT-5 mini?

Key differences include LLM Stats Score (55.9 vs 27.3), context window (1.0M vs 400K), input pricing ($10.00 vs $0.25/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Fable 5.1 and GPT-5 mini?

Claude Fable 5.1 is developed by Anthropic and GPT-5 mini is developed by OpenAI.