Kimi K2 Thinking vs Muse Spark 1.2
Updated October 21, 2026. 12 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Kimi K2 Thinking and Muse Spark 1.2 are level for coding, 63.4 against 65.1 on the Vibe Coding Index, so price and context decide.
Pick Kimi K2 Thinking when output tokens cost 1.7x less, or when a solved task costs $0.61 against $0.64. Pick Muse Spark 1.2 when the context window is larger, 1.05M against 262K tokens, or when what matters is SWE-bench Verified (Vals AI) or WeirdML, where it leads.
- Shared results
- 12
- Kimi K2 Thinking only
- 18
- Muse Spark 1.2 only
- 85
- Like-for-like categories
- 6 of 9
Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, four public coding benchmarks
No call
Level: 63.4 against 65.1, inside 2 points.
1 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
Muse Spark 1.2
Muse Spark 1.2 leads, 39.6 against 22.0.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Muse Spark 1.2 has a AA Agentic Index result, 43.2.
Directional only
Reasoning
GPQA Diamond
No call
Only Kimi K2 Thinking has a GPQA Diamond result, 78.5%.
Directional only
Math
AIME
No call
Only Kimi K2 Thinking has a AIME result, 85.4%.
Directional only
Knowledge
MMLU Pro
Muse Spark 1.2
Muse Spark 1.2 leads, 88.3% against 81.1%.
Same board, both measured
Web design
Design Arena: websites
Muse Spark 1.2
Muse Spark 1.2 leads, 1313 against 1113.
Same board, both measured
Long documents
Listed context window
Muse Spark 1.2
Muse Spark 1.2 takes 1.05M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Kimi K2 Thinking
Kimi K2 Thinking $0.0019, Muse Spark 1.2 $0.0034 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Kimi K2 Thinking
Kimi K2 Thinking $0.61, Muse Spark 1.2 $0.64.
Published attempt cost and pass rate
At a glance
- Coding index
- Kimi K2 Thinking 63.4 from 1 benchmark, Muse Spark 1.2 65.1 from 2 benchmarks.
- Widest category
- Web design, 25.0 points apart on average over 1 shared benchmark.
- Widest single gap
- SWE-bench Verified (Vals AI): Kimi K2 Thinking 60.2% against Muse Spark 1.2 86.6%, 26.4 points apart on a 0 to 100 scale.
- Output price
- Kimi K2 Thinking $2.50 against Muse Spark 1.2 $4.25 per million output tokens, 1.7x apart.
- Context window
- Kimi K2 Thinking takes 262K tokens, Muse Spark 1.2 1.05M.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | Kimi K2 Thinking | Bars | Muse Spark 1.2 | Ties |
|---|---|---|---|---|
| Coding | 0 | 2 | ||
| Intelligence | 0 | 2 | ||
| Reasoning | 0 | 2 | ||
| Knowledge | 0 | 4 | ||
| Web design | 0 | 1 | ||
| General | 0 | 1 | ||
| All shared boards | 0 | 12 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index02
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| SWE-bench Verified | 63.4% | Not measured | Only Kimi K2 Thinking measured |
| LiveBench coding | Not measured | 78.2% | Only Muse Spark 1.2 measured |
| LMArena WebDev | Not measured | 1534 | Only Muse Spark 1.2 measured |
| AA Coding Index | Not measured | 72.2 | Only Muse Spark 1.2 measured |
| LiveCodeBench (Vals AI) | 63.1% | Not measured | Only Kimi K2 Thinking measured |
| SWE-bench Verified (Vals AI) | 60.2% | 86.6% | Muse Spark 1.2 |
| Terminal-Bench 4 (Vals AI) | Not measured | 6.1% | Only Muse Spark 1.2 measured |
| Vibe Code Bench (Vals AI) | Not measured | 79.1% | Only Muse Spark 1.2 measured |
| Code migration (Vals AI) | Not measured | 29.9% | Only Muse Spark 1.2 measured |
| ProgramBench (Vals AI) | Not measured | 0.5% | Only Muse Spark 1.2 measured |
| IOI (Vals AI) | Not measured | 21.8% | Only Muse Spark 1.2 measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 69.7% | Only Muse Spark 1.2 measured |
| SkillsBench (Vals AI) | Not measured | 53.0% | Only Muse Spark 1.2 measured |
| CyberBench (Vals AI) | Not measured | 69.5% | Only Muse Spark 1.2 measured |
| LiveCodeBench (Artificial Analysis run) | 85.3% | Not measured | Only Kimi K2 Thinking measured |
| SciCode | Not measured | 57.4% | Only Muse Spark 1.2 measured |
| Terminal-Bench Hard (Artificial Analysis run) | 31.1% | Not measured | Only Kimi K2 Thinking measured |
| Terminal-Bench | 35.7% | Not measured | Only Kimi K2 Thinking measured |
| FrontierSWE | Not measured | 12.0% | Only Muse Spark 1.2 measured |
| WeirdML | 42.8% | 60.3% | Muse Spark 1.2 |
| ALE-Bench | 597.5 | Not measured | Only Kimi K2 Thinking measured |
| LMArena Text: coding | Not measured | 1505 | Only Muse Spark 1.2 measured |
| LMArena Text: software and IT | Not measured | 1505 | Only Muse Spark 1.2 measured |
| LMArena WebDev: React | Not measured | 1526 | Only Muse Spark 1.2 measured |
| LMArena WebDev: HTML | Not measured | 1543 | Only Muse Spark 1.2 measured |
| Neither model has a result on the other 13 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| AA Intelligence Index | 22.0 | 39.6 | Muse Spark 1.2 |
| Epoch Capabilities Index | 145.8 | 155.1 | Muse Spark 1.2 |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index20 boards, none shared
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 43.2 | Only Muse Spark 1.2 measured |
| Design Arena: agents building web apps | Not measured | 1222 | Only Muse Spark 1.2 measured |
| Design Arena: agents building full-stack apps | Not measured | 1210 | Only Muse Spark 1.2 measured |
| Design Arena: agents building mobile apps | Not measured | 1182 | Only Muse Spark 1.2 measured |
| Design Arena: agents building Android apps | Not measured | 1228 | Only Muse Spark 1.2 measured |
| Design Arena: agents building games | Not measured | 1179 | Only Muse Spark 1.2 measured |
| Design Arena: HTML slides | Not measured | 1135 | Only Muse Spark 1.2 measured |
| Design Arena: PowerPoint slides | Not measured | 1198 | Only Muse Spark 1.2 measured |
| LiveBench research | Not measured | 67.7% | Only Muse Spark 1.2 measured |
| LiveBench browser | Not measured | 36.0% | Only Muse Spark 1.2 measured |
| LiveBench long agentic | Not measured | 21.3% | Only Muse Spark 1.2 measured |
| SREBench (Vals AI) | Not measured | 0.0% | Only Muse Spark 1.2 measured |
| Finance Agent (Vals AI) | Not measured | 60.6% | Only Muse Spark 1.2 measured |
| Tax Agent Bench (Vals AI) | Not measured | 32.8% | Only Muse Spark 1.2 measured |
| Legal Research Bench (Vals AI) | Not measured | 43.8% | Only Muse Spark 1.2 measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 57.0% | Only Muse Spark 1.2 measured |
| BioMysteryBench (Vals AI) | Not measured | 64.8% | Only Muse Spark 1.2 measured |
| τ²-Bench Telecom | 93.0% | Not measured | Only Kimi K2 Thinking measured |
| APEX-Agents | Not measured | 45.4% | Only Muse Spark 1.2 measured |
| METR time horizons | 59.2% | Not measured | Only Kimi K2 Thinking measured |
| Neither model has a result on the other 19 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| GPQA Diamond | 78.5% | Not measured | Only Kimi K2 Thinking measured |
| LiveBench reasoning | Not measured | 90.0% | Only Muse Spark 1.2 measured |
| MMMU Pro (Vals AI) | Not measured | 86.1% | Only Muse Spark 1.2 measured |
| GPQA Diamond (Artificial Analysis run) | 83.8% | 90.4% | Muse Spark 1.2 |
| Humanity's Last Exam (Artificial Analysis run) | 23.8% | 45.5% | Muse Spark 1.2 |
| SimpleBench | Not measured | 74.5% | Only Muse Spark 1.2 measured |
| Chess puzzles | Not measured | 27.0% | Only Muse Spark 1.2 measured |
| LMArena Text: hard prompts | Not measured | 1489 | Only Muse Spark 1.2 measured |
| LMArena Text: expert | Not measured | 1475 | Only Muse Spark 1.2 measured |
| LMArena Text: hard prompts in English | Not measured | 1487 | Only Muse Spark 1.2 measured |
| LMArena Vision: diagrams | Not measured | 1317 | Only Muse Spark 1.2 measured |
| Neither model has a result on the other 10 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| AIME | 85.4% | Not measured | Only Kimi K2 Thinking measured |
| MGSM (Vals AI) | 90.2% | Not measured | Only Kimi K2 Thinking measured |
| AA Math Index | 94.7 | Not measured | Only Kimi K2 Thinking measured |
| AIME 2025 (Artificial Analysis run) | 94.7% | Not measured | Only Kimi K2 Thinking measured |
| ProofBench | Not measured | 43.0% | Only Muse Spark 1.2 measured |
| LMArena Text: math | Not measured | 1484 | Only Muse Spark 1.2 measured |
| LMArena Text: mathematical work | Not measured | 1480 | Only Muse Spark 1.2 measured |
| Neither model has a result on the other 6 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| MMLU Pro | 81.1% | 88.3% | Muse Spark 1.2 |
| LegalBench (Vals AI) | 80.2% | 85.3% | Muse Spark 1.2 |
| CaseLaw (Vals AI) | 65.7% | Not measured | Only Kimi K2 Thinking measured |
| CorpFin (Vals AI) | 60.6% | 70.9% | Muse Spark 1.2 |
| TaxEval (Vals AI) | 71.7% | 80.4% | Muse Spark 1.2 |
| MortgageTax (Vals AI) | Not measured | 65.4% | Only Muse Spark 1.2 measured |
| MedQA (Vals AI) | 92.6% | Not measured | Only Kimi K2 Thinking measured |
| MedCode (Vals AI) | Not measured | 49.4% | Only Muse Spark 1.2 measured |
| MMLU Pro (Artificial Analysis run) | 84.8% | Not measured | Only Kimi K2 Thinking measured |
| SimpleQA Verified | Not measured | 60.3% | Only Muse Spark 1.2 measured |
| LMArena Text: science | Not measured | 1500 | Only Muse Spark 1.2 measured |
| LMArena Text: medicine and healthcare | Not measured | 1496 | Only Muse Spark 1.2 measured |
| LMArena Text: legal and government | Not measured | 1517 | Only Muse Spark 1.2 measured |
| LMArena Text: business and finance | Not measured | 1484 | Only Muse Spark 1.2 measured |
| Neither model has a result on the other 3 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| Design Arena: websites | 1113 | 1313 | Muse Spark 1.2 |
| Design Arena: UI components | Not measured | 1300 | Only Muse Spark 1.2 measured |
| Design Arena: game dev | Not measured | 1302 | Only Muse Spark 1.2 measured |
| Design Arena: data viz | Not measured | 1334 | Only Muse Spark 1.2 measured |
| Design Arena: 3D | Not measured | 1301 | Only Muse Spark 1.2 measured |
| Design Arena: all code categories | Not measured | 1313 | Only Muse Spark 1.2 measured |
| Design Arena: SVG | Not measured | 1285 | Only Muse Spark 1.2 measured |
| Design Arena: ASCII art | Not measured | 1284 | Only Muse Spark 1.2 measured |
| LiveBench design | Not measured | 67.1% | Only Muse Spark 1.2 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| LiveBench data analysis | Not measured | 76.5% | Only Muse Spark 1.2 measured |
| Public Benefits Bench (Vals AI) | Not measured | 68.5% | Only Muse Spark 1.2 measured |
| SAGE (Vals AI) | Not measured | 47.7% | Only Muse Spark 1.2 measured |
| MedScribe (Vals AI) | Not measured | 90.1% | Only Muse Spark 1.2 measured |
| Vals Multimodal Index | Not measured | 69.8% | Only Muse Spark 1.2 measured |
| IFBench | 68.1% | Not measured | Only Kimi K2 Thinking measured |
| Long context reasoning (AA-LCR) | 72.0% | 79.0% | Muse Spark 1.2 |
| DTBench | Not measured | 94.7% | Only Muse Spark 1.2 measured |
| LMCA | Not measured | 48.4% | Only Muse Spark 1.2 measured |
| CL-bench | 17.6% | Not measured | Only Kimi K2 Thinking measured |
| LMArena Text | Not measured | 1482 | Only Muse Spark 1.2 measured |
| LMArena Text: instruction following | Not measured | 1462 | Only Muse Spark 1.2 measured |
| LMArena Text: creative writing | Not measured | 1436 | Only Muse Spark 1.2 measured |
| LMArena Vision | Not measured | 1304 | Only Muse Spark 1.2 measured |
| LMArena Text: English | Not measured | 1483 | Only Muse Spark 1.2 measured |
| LMArena Text: non-English | Not measured | 1476 | Only Muse Spark 1.2 measured |
| LMArena Text: Chinese | Not measured | 1509 | Only Muse Spark 1.2 measured |
| LMArena Text: Korean | Not measured | 1462 | Only Muse Spark 1.2 measured |
| LMArena Text: French | Not measured | 1495 | Only Muse Spark 1.2 measured |
| LMArena Text: Spanish | Not measured | 1484 | Only Muse Spark 1.2 measured |
| LMArena Text: Russian | Not measured | 1483 | Only Muse Spark 1.2 measured |
| LMArena Text: multi-turn | Not measured | 1502 | Only Muse Spark 1.2 measured |
| LMArena Text: longer queries | Not measured | 1473 | Only Muse Spark 1.2 measured |
| LMArena Text: writing and language | Not measured | 1453 | Only Muse Spark 1.2 measured |
| LMArena Text: entertainment and media | Not measured | 1443 | Only Muse Spark 1.2 measured |
| LMArena Vision: English | Not measured | 1291 | Only Muse Spark 1.2 measured |
| LMArena Vision: reading text | Not measured | 1313 | Only Muse Spark 1.2 measured |
| Neither model has a result on the other 19 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Kimi K2 Thinking | Muse Spark 1.2 | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
Kimi K2 Thinking costs less
Repository review
50K input + 3K output tokens
Kimi K2 Thinking costs less
Agent loop
200K input + 10K output tokens
Kimi K2 Thinking costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | MoonshotAI Kimi K2 Thinking | Meta Muse Spark 1.2 |
|---|---|---|
| Maker | Moonshot AI | Meta |
| Weights | Open weights | No public weights listed |
| Released | November 6, 2025 | August 5, 2026 |
| Context window | 262K | 1.05M |
| Input $/Mtok | $0.60 | $1.25 |
| Output $/Mtok | $2.50 | $4.25 |
| Coding index | 63.4 | 65.1 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | $0.61 | $0.64 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Kimi K2 Thinking better than Muse Spark 1.2 for coding?
Kimi K2 Thinking and Muse Spark 1.2 are level for coding, 63.4 against 65.1 on the Vibe Coding Index, so price and context decide. Pick Kimi K2 Thinking when output tokens cost 1.7x less, or when a solved task costs $0.61 against $0.64. Pick Muse Spark 1.2 when the context window is larger, 1.05M against 262K tokens, or when what matters is SWE-bench Verified (Vals AI) or WeirdML, where it leads.
Which is cheaper, Kimi K2 Thinking or Muse Spark 1.2?
Kimi K2 Thinking costs $0.60 per million input tokens and $2.50 per million output tokens; Muse Spark 1.2 costs $1.25 and $4.25. Per solved SWE-bench Verified task, Kimi K2 Thinking costs $0.61 and Muse Spark 1.2 $0.64.
Which has the bigger context window, Kimi K2 Thinking or Muse Spark 1.2?
Muse Spark 1.2, with 1.05M tokens against 262K.
How many benchmarks is the Kimi K2 Thinking vs Muse Spark 1.2 comparison based on?
12 benchmarks have a result for both models as of October 21, 2026. Kimi K2 Thinking's coding index rests on 1 independent benchmark and Muse Spark 1.2's on 2. Where only one model has a result, the page says so instead of naming a winner.