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Claude Fable 5.1 vs GPT-4.1

Claude Fable 5.1 leads the LLM Stats Score 57.0 to 18.3. GPT-4.1 is 5.7x cheaper per token.

Anthropic · OpenAI · Updated for 2026

Which is better?

Claude Fable 5.1 leads the overall LLM Stats Score 57.0 to 18.3, ranking #1 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-4.1 is roughly 5.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-4.1 also accepts a larger context window (1,047,576 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 57.0 and ranks #1 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results
  • you want the most recent training data — it shipped Sep 2026

Choose GPT-4.1

  • cost matters — it's about 5.7x cheaper per token
  • you process long inputs — it offers a 1,047,576 token context window

At a glance

The differences that matter most.

Core performance indexes
57.0
#1
18.3
#202
54.5
#4
18.7
#194
37.0
#17
5.3
#194
Cost, coverage & limits
Benchmark wins
1 of 1
0 of 1
Input price
$10.00 / M
$2.00 / M
Output price
$50.00 / M
$8.00 / M
Context window
1,000,000
1,047,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Fable 5.1
GPT-4.1
40.8#1
9.8#122
31.6#8
11.7#107
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

7 reported for Claude Fable 5.1 · 29 for GPT-4.1

1 shared

Claude Fable 5.1 outperforms in 1 benchmarks (Humanity's Last Exam), while GPT-4.1 is better at 0 benchmarks.

Claude Fable 5.1 significantly outperforms across most benchmarks.

Thu Sep 03 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

GPT-4.1 costs less

For input processing, Claude Fable 5.1 ($10.00/1M tokens) is 5.0x more expensive than GPT-4.1 ($2.00/1M tokens).

For output processing, Claude Fable 5.1 ($50.00/1M tokens) is 6.3x more expensive than GPT-4.1 ($8.00/1M tokens).

In conclusion, Claude Fable 5.1 is more expensive than GPT-4.1.*

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

Lowest available price from all providers
Thu Sep 03 2026 • llm-stats.com
Anthropic
Claude Fable 5.1
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
OpenAI
GPT-4.1
Input tokens$2.00
Output tokens$8.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

GPT-4.1 accepts 1,047,576 input tokens compared to Claude Fable 5.1's 1,000,000 tokens. Claude Fable 5.1 can generate longer responses up to 128,000 tokens, while GPT-4.1 is limited to 32,768 tokens.

Anthropic
Claude Fable 5.1
Input1,000,000 tokens
Output128,000 tokens
OpenAI
GPT-4.1
Input1,047,576 tokens
Output32,768 tokens
Thu Sep 03 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Fable 5.1 and GPT-4.1 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-4.1

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-4.1

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Fable 5.1 was released on 2026-09-01, while GPT-4.1 was released on 2025-04-14.

Claude Fable 5.1 is 17 months newer than GPT-4.1.

Claude Fable 5.1

Sep 1, 2026

1 days ago

1.4yr newer
GPT-4.1

Apr 14, 2025

1.4 years ago

Knowledge Cutoff

When training data ends

GPT-4.1 has a documented knowledge cutoff of 2024-06-01, while Claude Fable 5.1's cutoff date is not specified.

We can confirm GPT-4.1's training data extends to 2024-06-01, but cannot make a direct comparison without Claude Fable 5.1's cutoff date.

Claude Fable 5.1

GPT-4.1

Jun 2024

Provider Availability

Claude Fable 5.1 is available from Anthropic. GPT-4.1 is available from OpenAI.

Claude Fable 5.1

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

GPT-4.1

openai logo
OpenAI
Input Price:Input: $2.00/1MOutput Price:Output: $8.00/1M
* 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-4.1 side-by-side, then vote on the output you prefer.

Claude Fable 5.1
✓ Preferred
GPT-4.1
Open in Playground

FAQ

Common questions about Claude Fable 5.1 vs GPT-4.1.

Which is better, Claude Fable 5.1 or GPT-4.1?

Claude Fable 5.1 leads the LLM Stats Score 57.0 to 18.3. Claude Fable 5.1 is made by Anthropic and GPT-4.1 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-4.1 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-4.1 scores MMLU: 90.2%, CharXiv-D: 87.9%, IFEval: 87.4%, MMMLU: 87.3%, MMMU: 74.8%.

Is Claude Fable 5.1 cheaper than GPT-4.1?

GPT-4.1 is 5.0x cheaper for input tokens. Claude Fable 5.1 costs $10.00/M input and $50.00/M output via anthropic. GPT-4.1 costs $2.00/M input and $8.00/M output via openai.

What are the context window sizes for Claude Fable 5.1 and GPT-4.1?

Claude Fable 5.1 supports 1.0M tokens and GPT-4.1 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 5.1 and GPT-4.1?

Key differences include LLM Stats Score (57.0 vs 18.3), context window (1.0M vs 1.0M), input pricing ($10.00 vs $2.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Fable 5.1 and GPT-4.1?

Claude Fable 5.1 is developed by Anthropic and GPT-4.1 is developed by OpenAI.