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Kimi K2 Instruct vs Muse Spark Open

Muse Spark Open leads the LLM Stats Score 44.9 to 21.6. Kimi K2 Instruct is 4.0x cheaper per token.

Moonshot AI · Meta · Updated for 2026

Which is better?

Muse Spark Open leads the overall LLM Stats Score 44.9 to 21.6, 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.

On price, Kimi K2 Instruct is roughly 4.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Muse Spark Open also accepts a larger context window (1,048,576 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 Kimi K2 Instruct

  • cost matters — it's about 4.0x cheaper per token

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 process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Oct 2026

At a glance

The differences that matter most.

Core performance indexes
21.6
#206
44.9
#43
21.7
#195
45.2
#39
12.1
#168
33.0
#42
-1.1
#200
30.6
#43
Cost, coverage & limits
Benchmark wins
0 of 1
1 of 1
Input price
$0.50 / M
$1.25 / M
Output price
$0.50 / M
$4.25 / M
Context window
200,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Kimi K2 Instruct
Muse Spark Open
22.1#149
31.6#69
6.3#163
23.3#44
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

38 reported for Kimi K2 Instruct · 17 for Muse Spark Open

1 shared

Kimi K2 Instruct 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

Pricing Analysis

Price comparison per million tokens

Kimi K2 Instruct costs less

For input processing, Kimi K2 Instruct ($0.50/1M tokens) is 2.5x cheaper than Muse Spark Open ($1.25/1M tokens).

For output processing, Kimi K2 Instruct ($0.50/1M tokens) is 8.5x cheaper than Muse Spark Open ($4.25/1M tokens).

In conclusion, Muse Spark Open is more expensive than Kimi K2 Instruct.*

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

Lowest available price from all providers
Mon Oct 19 2026 • llm-stats.com
Moonshot AI
Kimi K2 Instruct
Input tokens$0.50
Output tokens$0.50
Best providerFireworks
Meta
Muse Spark Open
Input tokens$1.25
Output tokens$4.25
Best providerTogether
Notice missing or incorrect data?

Model Size

Parameter count comparison

184.0B diff

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

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

Context Window

Maximum input and output token capacity

Muse Spark Open accepts 1,048,576 input tokens compared to Kimi K2 Instruct's 200,000 tokens. Muse Spark Open can generate longer responses up to 1,048,576 tokens, while Kimi K2 Instruct is limited to 200,000 tokens.

Moonshot AI
Kimi K2 Instruct
Input200,000 tokens
Output200,000 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 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

Text
Images
Audio
Video

Muse Spark Open

Text
Images
Audio
Video

License

Usage and distribution terms

Kimi K2 Instruct 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

MIT

Open weights

Muse Spark Open

Muse Model License

Open weights

Release Timeline

When each model was launched

Kimi K2 Instruct was released on 2025-07-11, while Muse Spark Open was released on 2026-10-15.

Muse Spark Open is 15 months newer than Kimi K2 Instruct.

Kimi K2 Instruct

Jul 11, 2025

1.3 years ago

Muse Spark Open

Oct 15, 2026

4 days ago

1.3yr 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

Provider Availability

Kimi K2 Instruct is available from Fireworks, Novita. Muse Spark Open is available from Together.

Kimi K2 Instruct

fireworks logo
Fireworks
Input Price:Input: $0.50/1MOutput Price:Output: $0.50/1M
novita logo
Novita
Input Price:Input: $0.57/1MOutput Price:Output: $2.30/1M

Muse Spark Open

together logo
Together
Input Price:Input: $1.25/1MOutput Price:Output: $4.25/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

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

Kimi K2 Instruct
✓ Preferred
Muse Spark Open
Open in Playground

FAQ

Common questions about Kimi K2 Instruct vs Muse Spark Open.

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

Muse Spark Open leads the LLM Stats Score 44.9 to 21.6. Kimi K2 Instruct 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 compare to Muse Spark Open in benchmarks?

Kimi K2 Instruct scores MATH-500: 97.4%, GSM8k: 97.3%, CBNSL: 95.6%, HumanEval: 93.3%, MMLU-Redux: 92.7%. Muse Spark Open scores MCP Atlas: 89.2%, GPQA: 89.0%, OSWorld-Verified: 80.4%, BabyVision: 80.2%, Terminal-Bench 2.1: 76.4%.

Is Kimi K2 Instruct cheaper than Muse Spark Open?

Kimi K2 Instruct is 2.5x cheaper for input tokens. Kimi K2 Instruct costs $0.50/M input and $0.50/M output via fireworks. Muse Spark Open costs $1.25/M input and $4.25/M output via together.

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

Kimi K2 Instruct supports 200K 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 and Muse Spark Open?

Key differences include LLM Stats Score (21.6 vs 44.9), context window (200K vs 1.0M), input pricing ($0.50 vs $1.25/M), 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 and Muse Spark Open?

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