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Claude Fable 5.1 vs Kimi K2 0905

Claude Fable 5.1 leads the LLM Stats Score 56.8 to 21.8. Kimi K2 0905 is 18.6x cheaper per token.

Anthropic · Moonshot AI · Updated for 2026

Which is better?

Claude Fable 5.1 leads the overall LLM Stats Score 56.8 to 21.8, ranking #2 overall.

On price, Kimi K2 0905 is roughly 18.6x 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 56.8 and ranks #2 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • 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 Kimi K2 0905

  • cost matters — it's about 18.6x cheaper per token

At a glance

The differences that matter most.

Claude Fable 5.1
Anthropic
Kimi K2 0905
Moonshot AI
Core performance indexes
LLM Stats Score
56.8
#2
21.8
#173
Reasoning
53.9
#5
22.2
#162
Coding
36.0
#22
19.5
#98
Cost, coverage & limits
Benchmark wins
—
—
Input price
$10.00 / M
$0.60 / M
Output price
$50.00 / M
$2.50 / M
Context window
1,000,000
262,144

Individual benchmarks

7 reported for Claude Fable 5.1 · 6 for Kimi K2 0905

No common benchmarks found

Claude Fable 5.1 and Kimi K2 0905don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Kimi K2 0905 costs less

For input processing, Claude Fable 5.1 ($10.00/1M tokens) is 16.7x more expensive than Kimi K2 0905 ($0.60/1M tokens).

For output processing, Claude Fable 5.1 ($50.00/1M tokens) is 20.0x more expensive than Kimi K2 0905 ($2.50/1M tokens).

In conclusion, Claude Fable 5.1 is more expensive than Kimi K2 0905.*

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

Lowest available price from all providers
Fri Sep 04 2026 • llm-stats.com
Anthropic
Claude Fable 5.1
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
Moonshot AI
Kimi K2 0905
Input tokens$0.60
Output tokens$2.50
Best providerNovita
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 Kimi K2 0905's 262,144 tokens. Kimi K2 0905 can generate longer responses up to 262,144 tokens, while Claude Fable 5.1 is limited to 128,000 tokens.

Anthropic
Claude Fable 5.1
Input1,000,000 tokens
Output128,000 tokens
Moonshot AI
Kimi K2 0905
Input262,144 tokens
Output262,144 tokens
Fri Sep 04 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Fable 5.1 supports multimodal inputs, whereas Kimi K2 0905 does not.

Claude Fable 5.1 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Fable 5.1

Text
Images
Audio
Video

Kimi K2 0905

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

Kimi K2 0905

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Fable 5.1 was released on 2026-09-01, while Kimi K2 0905 was released on 2025-09-05.

Claude Fable 5.1 is 12 months newer than Kimi K2 0905.

Claude Fable 5.1

Sep 1, 2026

3 days ago

12mo newer
Kimi K2 0905

Sep 5, 2025

12 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 5.1 is available from Anthropic. Kimi K2 0905 is available from Novita.

Claude Fable 5.1

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

Kimi K2 0905

novita logo
Novita
Input Price:Input: $0.60/1MOutput Price:Output: $2.50/1M
* 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 Kimi K2 0905 side-by-side, then vote on the output you prefer.

Claude Fable 5.1
✓ Preferred
Kimi K2 0905
Open in Playground

FAQ

Common questions about Claude Fable 5.1 vs Kimi K2 0905.

Which is better, Claude Fable 5.1 or Kimi K2 0905?

Claude Fable 5.1 leads the LLM Stats Score 56.8 to 21.8. Claude Fable 5.1 is made by Anthropic and Kimi K2 0905 is made by Moonshot AI. 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 Kimi K2 0905 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%. Kimi K2 0905 scores HumanEval: 94.5%, MMLU: 90.2%, MATH: 89.1%, MMLU-Pro: 82.5%, GPQA: 75.8%.

Is Claude Fable 5.1 cheaper than Kimi K2 0905?

Kimi K2 0905 is 16.7x cheaper for input tokens. Claude Fable 5.1 costs $10.00/M input and $50.00/M output via anthropic. Kimi K2 0905 costs $0.60/M input and $2.50/M output via novita.

What are the context window sizes for Claude Fable 5.1 and Kimi K2 0905?

Claude Fable 5.1 supports 1.0M tokens and Kimi K2 0905 supports 262K 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 Kimi K2 0905?

Key differences include LLM Stats Score (56.8 vs 21.8), context window (1.0M vs 262K), input pricing ($10.00 vs $0.60/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Fable 5.1 and Kimi K2 0905?

Claude Fable 5.1 is developed by Anthropic and Kimi K2 0905 is developed by Moonshot AI.

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