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Claude Fable 5.1 vs DiffusionGemma 26B-A4B

Claude Fable 5.1 leads the LLM Stats Score 55.9 to 19.4.

Anthropic · Google · Updated for 2026

Which is better?

Claude Fable 5.1 leads the overall LLM Stats Score 55.9 to 19.4, 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.

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 and agents — 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 DiffusionGemma 26B-A4B

  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Fable 5.1
Anthropic
DiffusionGemma 26B-A4B
Google
Core performance indexes
LLM Stats Score
55.9
#2
19.4
#204
Reasoning
53.0
#5
19.1
#201
Agents
41.8
#2
0.5
#170
Cost, coverage & limits
Benchmark wins
1 of 1
0 of 1
Input price
$10.00 / M
— / M
Output price
$50.00 / M
— / M
Context window
1,000,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Claude Fable 5.1
DiffusionGemma 26B-A4B
Vision
41.8#1
10.6#118
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

7 reported for Claude Fable 5.1 · 14 for DiffusionGemma 26B-A4B

1 shared

Claude Fable 5.1 outperforms in 1 benchmarks (Humanity's Last Exam), while DiffusionGemma 26B-A4B is better at 0 benchmarks.

Claude Fable 5.1 significantly outperforms across most benchmarks.

Fri Sep 11 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Claude Fable 5.1 specifies input context (1,000,000 tokens). Only Claude Fable 5.1 specifies output context (128,000 tokens).

Anthropic
Claude Fable 5.1
Input1,000,000 tokens
Output128,000 tokens
Google
DiffusionGemma 26B-A4B
Input- tokens
Output- tokens
Fri Sep 11 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Fable 5.1 and DiffusionGemma 26B-A4B 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

DiffusionGemma 26B-A4B

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Fable 5.1 is licensed under a proprietary license, while DiffusionGemma 26B-A4B uses Apache 2.0.

License differences may affect how you can use these models in commercial or open-source projects.

Claude Fable 5.1

Proprietary

Closed source

DiffusionGemma 26B-A4B

Apache 2.0

Open weights

Release Timeline

When each model was launched

Claude Fable 5.1 was released on 2026-09-01, while DiffusionGemma 26B-A4B was released on 2026-06-10.

Claude Fable 5.1 is 3 months newer than DiffusionGemma 26B-A4B.

Claude Fable 5.1

Sep 1, 2026

1 weeks ago

2mo newer
DiffusionGemma 26B-A4B

Jun 10, 2026

3 months ago

Knowledge Cutoff

When training data ends

DiffusionGemma 26B-A4B has a documented knowledge cutoff of 2025-01-01, while Claude Fable 5.1's cutoff date is not specified.

We can confirm DiffusionGemma 26B-A4B's training data extends to 2025-01-01, but cannot make a direct comparison without Claude Fable 5.1's cutoff date.

Claude Fable 5.1

—

DiffusionGemma 26B-A4B

Jan 2025

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude Fable 5.1 and DiffusionGemma 26B-A4B side-by-side, then vote on the output you prefer.

Claude Fable 5.1
✓ Preferred
DiffusionGemma 26B-A4B
Open in Playground

FAQ

Common questions about Claude Fable 5.1 vs DiffusionGemma 26B-A4B.

Which is better, Claude Fable 5.1 or DiffusionGemma 26B-A4B?

Claude Fable 5.1 leads the LLM Stats Score 55.9 to 19.4. Claude Fable 5.1 is made by Anthropic and DiffusionGemma 26B-A4B is made by Google. 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 DiffusionGemma 26B-A4B 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%. DiffusionGemma 26B-A4B scores MMMLU: 81.5%, MMLU-Pro: 77.6%, GPQA: 73.2%, MathVision: 70.5%, AIME 2026: 69.1%.

What are the context window sizes for Claude Fable 5.1 and DiffusionGemma 26B-A4B?

Claude Fable 5.1 supports 1.0M tokens and DiffusionGemma 26B-A4B supports an unknown number of 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 DiffusionGemma 26B-A4B?

Key differences include LLM Stats Score (55.9 vs 19.4), licensing (Proprietary vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Fable 5.1 and DiffusionGemma 26B-A4B?

Claude Fable 5.1 is developed by Anthropic and DiffusionGemma 26B-A4B is developed by Google.

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