Claude Sonnet 5.5 vs Kimi K2.7 Code
Updated October 21, 2026. 31 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
vs boards won of 31 shared
Decision reading
Pick Claude Sonnet 5.5 for coding: it scores 88.9 on the Vibe Coding Index against 39.1 for Kimi K2.7 Code.
Pick Kimi K2.7 Code when output tokens cost 3.0x less.
Model AClaude Sonnet 5.5Anthropic88.9/1002 independent benchmarksNo cost per solved taskModel BKimi K2.7 CodeMoonshot AI39.1/1001 independent benchmark$0.35 per solved task
- Shared results
- 31
- Claude Sonnet 5.5 only
- 64
- Kimi K2.7 Code only
- 20
- Like-for-like categories
- 8 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
Claude Sonnet 5.5
Claude Sonnet 5.5 scores 88.9 against 39.1.
2 and 1 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 56.0 against 25.8.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Kimi K2.7 Code has a AA Agentic Index result, 21.0.
Directional only
Web design
Design Arena: websites
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 1326 against 1264.
Same board, both measured
General
Vals Index
No call
Only Claude Sonnet 5.5 has a Vals Index result, 70.8%.
Directional only
Long documents
Listed context window
Claude Sonnet 5.5
Claude Sonnet 5.5 takes 1M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Kimi K2.7 Code
Claude Sonnet 5.5 $0.0070, Kimi K2.7 Code $0.0023 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Kimi K2.7 Code has the number, $0.35.
Directional only
At a glance
- Coding index
- Claude Sonnet 5.5 88.9 from 2 benchmarks, Kimi K2.7 Code 39.1 from 1 benchmark.
- Widest category
- Math, 35.8 points apart on average over 3 shared benchmarks.
- Widest single gap
- FrontierMath, tier 4: Claude Sonnet 5.5 80.5% against Kimi K2.7 Code 12.2%, 68.3 points apart on a 0 to 100 scale.
- Output price
- Claude Sonnet 5.5 $10.00 against Kimi K2.7 Code $3.35 per million output tokens, 3.0x apart.
- Context window
- Claude Sonnet 5.5 takes 1M tokens, Kimi K2.7 Code 262K.
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 | Claude Sonnet 5.5 | Bars | Kimi K2.7 Code | Ties |
|---|---|---|---|---|
| Coding | 11 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 4 | 0 | ||
| Reasoning | 3 | 0 | ||
| Math | 3 | 0 | ||
| Knowledge | 1 | 0 | ||
| Web design | 6 | 0 | ||
| General | 1 | 0 | ||
| All shared boards | 31 | 0 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index110
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | Leader |
|---|---|---|---|
| LiveBench coding | 94.7% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev | 1768 | 1474 | Claude Sonnet 5.5 |
| AA Coding Index | Not measured | 60.8 | Only Kimi K2.7 Code measured |
| LiveCodeBench (Vals AI) | Not measured | 82.0% | Only Kimi K2.7 Code measured |
| SWE-bench Verified (Vals AI) | Not measured | 78.2% | Only Kimi K2.7 Code measured |
| Terminal-Bench 4 (Vals AI) | 64.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Vibe Code Bench (Vals AI) | 92.4% | 47.2% | Claude Sonnet 5.5 |
| Code migration (Vals AI) | 69.8% | 25.4% | Claude Sonnet 5.5 |
| ProgramBench (Vals AI) | 6.5% | 0.0% | Claude Sonnet 5.5 |
| IOI (Vals AI) | 83.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | 83.2% | 67.0% | Claude Sonnet 5.5 |
| SWE-bench Multimodal (Vals AI) | 58.3% | Not measured | Only Claude Sonnet 5.5 measured |
| SkillsBench (Vals AI) | Not measured | 50.0% | Only Kimi K2.7 Code measured |
| CyberBench (Vals AI) | 59.6% | Not measured | Only Claude Sonnet 5.5 measured |
| SciCode | 61.0% | 47.8% | Claude Sonnet 5.5 |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 44.7% | Only Kimi K2.7 Code measured |
| FrontierCode | 52.1% | 30.1% | Claude Sonnet 5.5 |
| FrontierSWE | 61.9% | Not measured | Only Claude Sonnet 5.5 measured |
| WeirdML | Not measured | 54.1% | Only Kimi K2.7 Code measured |
| ALE-Bench | 1819.1 | 886.2 | Claude Sonnet 5.5 |
| LMArena Text: coding | 1513 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: software and IT | 1504 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev: React | 1817 | 1475 | Claude Sonnet 5.5 |
| LMArena WebDev: HTML | 1741 | 1451 | Claude Sonnet 5.5 |
| LMArena WebDev: from an image | 1737 | 1513 | Claude Sonnet 5.5 |
| Neither model has a result on the other 13 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | Leader |
|---|---|---|---|
| AA Intelligence Index | 56.0 | 25.8 | Claude Sonnet 5.5 |
| Epoch Capabilities Index | 166.2 | 150.1 | Claude Sonnet 5.5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 21.0 | Only Kimi K2.7 Code measured |
| Design Arena: agents building web apps | 1303 | 1176 | Claude Sonnet 5.5 |
| Design Arena: agents building full-stack apps | Not measured | 1175 | Only Kimi K2.7 Code measured |
| Design Arena: agents building mobile apps | 1265 | 1143 | Claude Sonnet 5.5 |
| Design Arena: agents building Android apps | Not measured | 1143 | Only Kimi K2.7 Code measured |
| Design Arena: agents building Godot games | Not measured | 1147 | Only Kimi K2.7 Code measured |
| Design Arena: agents building games | Not measured | 1130 | Only Kimi K2.7 Code measured |
| Design Arena: HTML slides | Not measured | 1201 | Only Kimi K2.7 Code measured |
| Design Arena: PowerPoint slides | Not measured | 1154 | Only Kimi K2.7 Code measured |
| Design Arena: spreadsheets | 1245 | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench research | 83.6% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench browser | 84.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench long agentic | 78.8% | Not measured | Only Claude Sonnet 5.5 measured |
| SREBench (Vals AI) | 30.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Finance Agent (Vals AI) | 58.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Tax Agent Bench (Vals AI) | 42.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Legal Research Bench (Vals AI) | 48.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 10.4% | Not measured | Only Claude Sonnet 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 75.7% | Not measured | Only Claude Sonnet 5.5 measured |
| BioMysteryBench (Vals AI) | 81.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Terminal-Bench-Science (Vals AI) | 47.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Vals Science Index | 59.1% | Not measured | Only Claude Sonnet 5.5 measured |
| τ²-Bench Telecom | Not measured | 90.1% | Only Kimi K2.7 Code measured |
| APEX-Agents | 75.5% | 37.6% | Claude Sonnet 5.5 |
| SpireClimb | 1.3% | Not measured | Only Claude Sonnet 5.5 measured |
| Vending-Bench 2 | $11,165 | $5,083 | Claude Sonnet 5.5 |
| Neither model has a result on the other 13 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | Leader |
|---|---|---|---|
| LiveBench reasoning | 91.6% | Not measured | Only Claude Sonnet 5.5 measured |
| MysteryMechanism (Vals AI) | 49.1% | Not measured | Only Claude Sonnet 5.5 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 89.6% | Only Kimi K2.7 Code measured |
| Humanity's Last Exam (Artificial Analysis run) | 55.0% | 35.0% | Claude Sonnet 5.5 |
| GPQA Diamond (Epoch AI run) | 95.6% | 87.9% | Claude Sonnet 5.5 |
| SimpleBench | Not measured | 57.9% | Only Kimi K2.7 Code measured |
| Chess puzzles | 59.0% | 14.0% | Claude Sonnet 5.5 |
| Mystery game puzzles | 65.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: hard prompts | 1494 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: expert | 1531 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: hard prompts in English | 1502 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: diagrams | 1329 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: homework | 1331 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 8 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | 95.6% | Claude Sonnet 5.5 |
| FrontierMath, tiers 1 to 3 | 88.8% | 54.0% | Claude Sonnet 5.5 |
| FrontierMath, tier 4 | 80.5% | 12.2% | Claude Sonnet 5.5 |
| ProofBench | 100.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: math | 1497 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: mathematical work | 1510 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | Leader |
|---|---|---|---|
| MedCode (Vals AI) | 52.9% | Not measured | Only Claude Sonnet 5.5 measured |
| SimpleQA Verified | 46.5% | 36.5% | Claude Sonnet 5.5 |
| LMArena Text: science | 1483 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: medicine and healthcare | 1464 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: legal and government | 1483 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: business and finance | 1468 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 11 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | Leader |
|---|---|---|---|
| Design Arena: websites | 1326 | 1264 | Claude Sonnet 5.5 |
| Design Arena: UI components | 1367 | 1259 | Claude Sonnet 5.5 |
| Design Arena: game dev | 1469 | 1220 | Claude Sonnet 5.5 |
| Design Arena: data viz | 1389 | 1226 | Claude Sonnet 5.5 |
| Design Arena: 3D | 1458 | 1241 | Claude Sonnet 5.5 |
| Design Arena: all code categories | 1364 | 1253 | Claude Sonnet 5.5 |
| Design Arena: SVG | Not measured | 1176 | Only Kimi K2.7 Code measured |
| Design Arena: ASCII art | Not measured | 1196 | Only Kimi K2.7 Code measured |
| LiveBench design | 85.0% | Not measured | Only Claude Sonnet 5.5 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | Leader |
|---|---|---|---|
| Vals Index | 70.8% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench data analysis | 59.5% | Not measured | Only Claude Sonnet 5.5 measured |
| Public Benefits Bench (Vals AI) | 67.2% | Not measured | Only Claude Sonnet 5.5 measured |
| SAGE (Vals AI) | 51.8% | Not measured | Only Claude Sonnet 5.5 measured |
| MedScribe (Vals AI) | 91.1% | Not measured | Only Claude Sonnet 5.5 measured |
| IFBench | Not measured | 63.1% | Only Kimi K2.7 Code measured |
| Long context reasoning (AA-LCR) | 82.7% | 79.3% | Claude Sonnet 5.5 |
| DTBench | 97.3% | Not measured | Only Claude Sonnet 5.5 measured |
| LMCA | 68.3% | Not measured | Only Claude Sonnet 5.5 measured |
| Surface Evolver Bench | Not measured | 48.8% | Only Kimi K2.7 Code measured |
| Furniture assembly | 75.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text | 1473 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: instruction following | 1492 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: creative writing | 1467 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision | 1287 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: English | 1484 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: non-English | 1456 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Chinese | 1535 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: French | 1499 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Spanish | 1451 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Russian | 1454 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: multi-turn | 1465 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: longer queries | 1495 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: writing and language | 1474 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: entertainment and media | 1461 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: English | 1289 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: reading text | 1297 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: creative writing | 1242 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 18 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Kimi K2.7 Code | 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
Claude Sonnet 5.5$0.0070Fits in one request
Kimi K2.7 Code$0.0023Fits in one request
Kimi K2.7 Code costs less
Repository review
50K input + 3K output tokens
Claude Sonnet 5.5$0.130Fits in one request
Kimi K2.7 Code$0.044Fits in one request
Kimi K2.7 Code costs less
Agent loop
200K input + 10K output tokens
Claude Sonnet 5.5$0.500Fits in one request
Kimi K2.7 Code$0.168Fits in one request
Kimi K2.7 Code 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 | Anthropic Claude Sonnet 5.5 | MoonshotAI Kimi K2.7 Code |
|---|---|---|
| Maker | Anthropic | Moonshot AI |
| Weights | No public weights listed | Open weights |
| Released | September 28, 2026 | June 12, 2026 |
| Context window | 1M | 262K |
| Input $/Mtok | $2.00 | $0.6712 |
| Output $/Mtok | $10.00 | $3.35 |
| Coding index | 88.9 | 39.1 |
| Independent measurements behind it | 2 | 1 |
| Cost per solved task | Not computable | $0.35 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Sonnet 5.5 better than Kimi K2.7 Code for coding?
Pick Claude Sonnet 5.5 for coding: it scores 88.9 on the Vibe Coding Index against 39.1 for Kimi K2.7 Code. Pick Kimi K2.7 Code when output tokens cost 3.0x less.
Which is cheaper, Claude Sonnet 5.5 or Kimi K2.7 Code?
Claude Sonnet 5.5 costs $2.00 per million input tokens and $10.00 per million output tokens; Kimi K2.7 Code costs $0.6712 and $3.35. Cost per solved task is known for Kimi K2.7 Code only.
Which has the bigger context window, Claude Sonnet 5.5 or Kimi K2.7 Code?
Claude Sonnet 5.5, with 1M tokens against 262K.
How many benchmarks is the Claude Sonnet 5.5 vs Kimi K2.7 Code comparison based on?
31 benchmarks have a result for both models as of October 21, 2026. Claude Sonnet 5.5's coding index rests on 2 independent benchmarks and Kimi K2.7 Code's on 1. Where only one model has a result, the page says so instead of naming a winner.