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Kimi K2-Instruct-0905 vs Muse Spark Open

Muse Spark Open leads the LLM Stats Score 44.9 to 21.3.

Moonshot AI · Meta · Updated for 2026

Which is better?

Muse Spark Open leads the overall LLM Stats Score 44.9 to 21.3, ranking #43 overall.

In the 1 individual benchmarks reported for both models, Muse Spark Open 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 Kimi K2-Instruct-0905

  • you are already invested in the Moonshot AI ecosystem

Choose Muse Spark Open

  • overall performance matters — it scores 44.9 and ranks #43 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 Oct 2026

At a glance

The differences that matter most.

Kimi K2-Instruct-0905
Moonshot AI
Muse Spark Open
Meta
Core performance indexes
LLM Stats Score
21.3
#210
44.9
#43
Reasoning
21.6
#199
45.2
#39
Coding
9.5
#191
33.0
#42
Agents
-4.2
#205
30.6
#43
Cost, coverage & limits
Benchmark wins
0 of 1
1 of 1
Input price
— / M
$1.25 / M
Output price
— / M
$4.25 / M
Context window
—
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Kimi K2-Instruct-0905
Muse Spark Open
Math
21.4#154
31.6#69
Tool use
6.3#162
23.3#44
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

29 reported for Kimi K2-Instruct-0905 · 17 for Muse Spark Open

1 shared

Kimi K2-Instruct-0905 outperforms in 0 benchmarks, while Muse Spark Open is better at 1 benchmark (GPQA).

Muse Spark Open significantly outperforms across most benchmarks.

Mon Oct 19 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Model Size

Parameter count comparison

184.0B diff

Kimi K2-Instruct-0905 has 184.0B more parameters than Muse Spark Open, making it 22.5% larger.

Moonshot AI
Kimi K2-Instruct-0905
1.0Tparameters
Meta
Muse Spark Open
816.0Bparameters
1000.0B
Kimi K2-Instruct-0905
816.0B
Muse Spark Open

Context Window

Maximum input and output token capacity

Only Muse Spark Open specifies input context (1,048,576 tokens). Only Muse Spark Open specifies output context (1,048,576 tokens).

Moonshot AI
Kimi K2-Instruct-0905
Input- tokens
Output- tokens
Meta
Muse Spark Open
Input1,048,576 tokens
Output1,048,576 tokens
Mon Oct 19 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Muse Spark Open supports multimodal inputs, whereas Kimi K2-Instruct-0905 does not.

Muse Spark Open can handle both text and other forms of data like images, making it suitable for multimodal applications.

Kimi K2-Instruct-0905

Text
Images
Audio
Video

Muse Spark Open

Text
Images
Audio
Video

License

Usage and distribution terms

Kimi K2-Instruct-0905 is licensed under MIT, while Muse Spark Open uses Muse Model License.

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

Kimi K2-Instruct-0905

MIT

Open weights

Muse Spark Open

Muse Model License

Open weights

Release Timeline

When each model was launched

Kimi K2-Instruct-0905 was released on 2025-09-05, while Muse Spark Open was released on 2026-10-15.

Muse Spark Open is 14 months newer than Kimi K2-Instruct-0905.

Kimi K2-Instruct-0905

Sep 5, 2025

1.1 years ago

Muse Spark Open

Oct 15, 2026

4 days ago

1.1yr newer

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

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Kimi K2-Instruct-0905 and Muse Spark Open side-by-side, then vote on the output you prefer.

Kimi K2-Instruct-0905
✓ Preferred
Muse Spark Open
Open in Playground

FAQ

Common questions about Kimi K2-Instruct-0905 vs Muse Spark Open.

Which is better, Kimi K2-Instruct-0905 or Muse Spark Open?

Muse Spark Open leads the LLM Stats Score 44.9 to 21.3. Kimi K2-Instruct-0905 is made by Moonshot AI and Muse Spark Open is made by Meta. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Kimi K2-Instruct-0905 compare to Muse Spark Open in benchmarks?

Kimi K2-Instruct-0905 scores MATH-500: 97.4%, MMLU-Redux: 92.7%, IFEval: 89.8%, AutoLogi: 89.5%, MMLU: 89.5%. Muse Spark Open scores MCP Atlas: 89.2%, GPQA: 89.0%, OSWorld-Verified: 80.4%, BabyVision: 80.2%, Terminal-Bench 2.1: 76.4%.

What are the context window sizes for Kimi K2-Instruct-0905 and Muse Spark Open?

Kimi K2-Instruct-0905 supports an unknown number of tokens and Muse Spark Open 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 Kimi K2-Instruct-0905 and Muse Spark Open?

Key differences include LLM Stats Score (21.3 vs 44.9), multimodal support (no vs yes), licensing (MIT vs Muse Model License). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi K2-Instruct-0905 and Muse Spark Open?

Kimi K2-Instruct-0905 is developed by Moonshot AI and Muse Spark Open is developed by Meta.

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