Kimi K2.5 vs Nemotron 3.5 Lightning
Kimi K2.5 leads Nemotron 3.5 Lightning on coding, 38.6 to 22.6 on the Vibe Coding Index, and Nemotron 3.5 Lightning costs 19.4x less per output token ($0.147 vs $2.85 per million). Updated October 21, 2026; 15 benchmarks have a result for both.
Kimi K2.5 or Nemotron 3.5 Lightning: which to pick
Pick Kimi K2.5 for coding: it scores 38.6 on the Vibe Coding Index against 22.6 for Nemotron 3.5 Lightning.
Pick Nemotron 3.5 Lightning for output tokens 19.4x cheaper ($0.147 vs $2.85 per million) and a lower cost per solved task ($0.06 against $0.24).
- Shared results
- 15
- Kimi K2.5 only
- 84
- Nemotron 3.5 Lightning only
- 5
- Like-for-like categories
- 6 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
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, six public coding benchmarks
Kimi K2.5
Kimi K2.5 scores 38.6 against 22.6.
3 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
Kimi K2.5
Kimi K2.5 leads, 23.5 against 12.9.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Nemotron 3.5 Lightning has a AA Agentic Index result, 3.5.
Directional only
Reasoning
GPQA Diamond
No call
Only Kimi K2.5 has a GPQA Diamond result, 84.1%.
Directional only
Math
AIME
No call
Only Kimi K2.5 has a AIME result, 95.6%.
Directional only
Knowledge
MMLU Pro
No call
Only Kimi K2.5 has a MMLU Pro result, 85.9%.
Directional only
Web design
Design Arena: websites
No call
Only Kimi K2.5 has a Design Arena: websites result, 1248.
Directional only
Long documents
Listed context window
No call
Both take 262K tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Nemotron 3.5 Lightning
Kimi K2.5 $0.0020, Nemotron 3.5 Lightning $0.0001 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Nemotron 3.5 Lightning
Kimi K2.5 $0.24, Nemotron 3.5 Lightning $0.06.
Published attempt cost and pass rate
At a glance
- Coding index
- Kimi K2.5 38.6 from 3 benchmarks, Nemotron 3.5 Lightning 22.6 from 2 benchmarks.
- Widest category
- General, 44.9 points apart on average over 2 shared benchmarks.
- Widest single gap
- MedScribe (Vals AI): Kimi K2.5 76.4% against Nemotron 3.5 Lightning 4.3%, 72.2 points apart on a 0 to 100 scale.
- Output price
- Kimi K2.5 $2.85 against Nemotron 3.5 Lightning $0.147 per million output tokens, 19.4x apart.
- Context window
- Both take 262K tokens.
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 K2.5 | Bars | Nemotron 3.5 Lightning | Ties |
|---|---|---|---|---|
| Coding | 6 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 3 | 0 | ||
| Reasoning | 2 | 0 | ||
| Knowledge | 1 | 0 | ||
| General | 2 | 0 | ||
| All shared boards | 15 | 0 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index60
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| SWE-bench Verified | 70.8% | Not measured | Only Kimi K2.5 measured |
| SWE-bench Multilingual | 67.3% | Not measured | Only Kimi K2.5 measured |
| LMArena WebDev | 1437 | Not measured | Only Kimi K2.5 measured |
| AA Coding Index | 46.8 | 26.8 | Kimi K2.5 |
| LiveCodeBench (Vals AI) | 83.9% | Not measured | Only Kimi K2.5 measured |
| SWE-bench Verified (Vals AI) | 70.0% | 52.8% | Kimi K2.5 |
| Vibe Code Bench (Vals AI) | 17.5% | 0.0% | Kimi K2.5 |
| Code migration (Vals AI) | 7.0% | 3.0% | Kimi K2.5 |
| ProgramBench (Vals AI) | Not measured | 0.0% | Only Nemotron 3.5 Lightning measured |
| Terminal-Bench 2.1 (Vals AI) | 42.0% | 10.9% | Kimi K2.5 |
| CyberBench (Vals AI) | Not measured | 29.5% | Only Nemotron 3.5 Lightning measured |
| SciCode | Not measured | 32.1% | Only Nemotron 3.5 Lightning measured |
| Terminal-Bench Hard (Artificial Analysis run) | 34.8% | Not measured | Only Kimi K2.5 measured |
| Terminal-Bench | 43.2% | Not measured | Only Kimi K2.5 measured |
| WeirdML | 45.6% | Not measured | Only Kimi K2.5 measured |
| ALE-Bench | 821.6 | 769.2 | Kimi K2.5 |
| LMArena Text: coding | 1483 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: software and IT | 1471 | Not measured | Only Kimi K2.5 measured |
| LMArena WebDev: React | 1429 | Not measured | Only Kimi K2.5 measured |
| LMArena WebDev: HTML | 1426 | Not measured | Only Kimi K2.5 measured |
| LMArena WebDev: from an image | 1439 | Not measured | Only Kimi K2.5 measured |
| Neither model has a result on the other 18 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| AA Intelligence Index | 23.5 | 12.9 | Kimi K2.5 |
| Epoch Capabilities Index | 148.1 | Not measured | Only Kimi K2.5 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 3.5 | Only Nemotron 3.5 Lightning measured |
| Design Arena: agents building web apps | 1136 | Not measured | Only Kimi K2.5 measured |
| Design Arena: agents building full-stack apps | 1114 | Not measured | Only Kimi K2.5 measured |
| Design Arena: agents building mobile apps | 1147 | Not measured | Only Kimi K2.5 measured |
| Design Arena: agents building Android apps | 1118 | Not measured | Only Kimi K2.5 measured |
| Design Arena: agents building Godot games | 1219 | Not measured | Only Kimi K2.5 measured |
| Finance Agent (Vals AI) | 35.8% | 18.5% | Kimi K2.5 |
| Tax Agent Bench (Vals AI) | Not measured | 2.6% | Only Nemotron 3.5 Lightning measured |
| Legal Research Bench (Vals AI) | 15.9% | 2.9% | Kimi K2.5 |
| Excel Modeling Benchmark (Vals AI) | 28.5% | 17.0% | Kimi K2.5 |
| τ²-Bench Telecom | 95.9% | Not measured | Only Kimi K2.5 measured |
| OSWorld | 63.3% | Not measured | Only Kimi K2.5 measured |
| Vending-Bench 2 | $1,198 | Not measured | Only Kimi K2.5 measured |
| Neither model has a result on the other 28 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| GPQA Diamond | 84.1% | Not measured | Only Kimi K2.5 measured |
| MMMU Pro (Vals AI) | 84.3% | Not measured | Only Kimi K2.5 measured |
| GPQA Diamond (Artificial Analysis run) | 87.9% | 74.3% | Kimi K2.5 |
| Humanity's Last Exam (Artificial Analysis run) | 30.7% | 10.6% | Kimi K2.5 |
| ARC-AGI | 65.3% | Not measured | Only Kimi K2.5 measured |
| ARC-AGI-2 | 11.8% | Not measured | Only Kimi K2.5 measured |
| SimpleBench | 46.8% | Not measured | Only Kimi K2.5 measured |
| LMArena Text: hard prompts | 1453 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: expert | 1466 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: hard prompts in English | 1460 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: diagrams | 1282 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: homework | 1297 | Not measured | Only Kimi K2.5 measured |
| Kagi LLM Benchmark | 78.5% | Not measured | Only Kimi K2.5 measured |
| Neither model has a result on the other 9 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index3 boards, none shared
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| AIME | 95.6% | Not measured | Only Kimi K2.5 measured |
| LMArena Text: math | 1470 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: mathematical work | 1473 | Not measured | Only Kimi K2.5 measured |
| Neither model has a result on the other 10 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| MMLU Pro | 85.9% | Not measured | Only Kimi K2.5 measured |
| CaseLaw (Vals AI) | 58.7% | Not measured | Only Kimi K2.5 measured |
| CorpFin (Vals AI) | 68.3% | 54.2% | Kimi K2.5 |
| TaxEval (Vals AI) | 74.2% | Not measured | Only Kimi K2.5 measured |
| MortgageTax (Vals AI) | 66.5% | Not measured | Only Kimi K2.5 measured |
| MedQA (Vals AI) | 94.4% | Not measured | Only Kimi K2.5 measured |
| MedCode (Vals AI) | 39.3% | Not measured | Only Kimi K2.5 measured |
| SimpleQA Verified | 34.3% | Not measured | Only Kimi K2.5 measured |
| LMArena Text: science | 1459 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: medicine and healthcare | 1448 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: legal and government | 1441 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: business and finance | 1427 | Not measured | Only Kimi K2.5 measured |
| Neither model has a result on the other 6 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| Design Arena: websites | 1248 | Not measured | Only Kimi K2.5 measured |
| Design Arena: UI components | 1236 | Not measured | Only Kimi K2.5 measured |
| Design Arena: game dev | 1207 | Not measured | Only Kimi K2.5 measured |
| Design Arena: data viz | 1219 | Not measured | Only Kimi K2.5 measured |
| Design Arena: 3D | 1205 | Not measured | Only Kimi K2.5 measured |
| Design Arena: all code categories | 1236 | Not measured | Only Kimi K2.5 measured |
| Design Arena: SVG | 1149 | Not measured | Only Kimi K2.5 measured |
| Design Arena: ASCII art | 1166 | Not measured | Only Kimi K2.5 measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| SAGE (Vals AI) | 49.9% | Not measured | Only Kimi K2.5 measured |
| MedScribe (Vals AI) | 76.4% | 4.3% | Kimi K2.5 |
| IFBench | 70.2% | Not measured | Only Kimi K2.5 measured |
| Long context reasoning (AA-LCR) | 78.0% | 60.3% | Kimi K2.5 |
| Fiction.LiveBench | 86.1% | Not measured | Only Kimi K2.5 measured |
| CL-bench | 19.3% | Not measured | Only Kimi K2.5 measured |
| CL-bench Life | 13.2% | Not measured | Only Kimi K2.5 measured |
| LMArena Text | 1445 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: instruction following | 1431 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: creative writing | 1422 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision | 1269 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: English | 1453 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: non-English | 1433 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: Chinese | 1494 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: German | 1441 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: Japanese | 1423 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: Korean | 1412 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: French | 1454 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: Spanish | 1450 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: Russian | 1435 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: Polish | 1445 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: multi-turn | 1444 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: longer queries | 1445 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: writing and language | 1425 | Not measured | Only Kimi K2.5 measured |
| LMArena Text: entertainment and media | 1417 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: English | 1274 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: Chinese | 1328 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: reading text | 1276 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: humor | 1284 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: captioning | 1257 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: recognizing things | 1285 | Not measured | Only Kimi K2.5 measured |
| LMArena Vision: creative writing | 1269 | Not measured | Only Kimi K2.5 measured |
| Neither model has a result on the other 14 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Kimi K2.5 | Nemotron 3.5 Lightning | 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
Nemotron 3.5 Lightning costs less
Repository review
50K input + 3K output tokens
Nemotron 3.5 Lightning costs less
Agent loop
200K input + 10K output tokens
Nemotron 3.5 Lightning 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 K2.5 | NVIDIA Nemotron 3.5 Lightning |
|---|---|---|
| Maker | Moonshot AI | NVIDIA |
| Weights | Open weights | Open weights |
| Released | January 27, 2026 | August 11, 2026 |
| Context window | 262K | 262K |
| Input $/Mtok | $0.532 | $0.0534 |
| Output $/Mtok | $2.85 | $0.147 |
| Coding index | 38.6 | 22.6 |
| Independent measurements behind it | 3 | 2 |
| Cost per solved task | $0.24 | $0.06 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Kimi K2.5 better than Nemotron 3.5 Lightning for coding?
Pick Kimi K2.5 for coding: it scores 38.6 on the Vibe Coding Index against 22.6 for Nemotron 3.5 Lightning. Pick Nemotron 3.5 Lightning for output tokens 19.4x cheaper ($0.147 vs $2.85 per million) and a lower cost per solved task ($0.06 against $0.24).
Which is cheaper, Kimi K2.5 or Nemotron 3.5 Lightning?
Kimi K2.5 costs $0.532 per million input tokens and $2.85 per million output tokens; Nemotron 3.5 Lightning costs $0.0534 and $0.147. Per solved SWE-bench Verified task, Kimi K2.5 costs $0.24 and Nemotron 3.5 Lightning $0.06.
Which has the bigger context window, Kimi K2.5 or Nemotron 3.5 Lightning?
Neither: both take 262K tokens.
How many benchmarks is the Kimi K2.5 vs Nemotron 3.5 Lightning comparison based on?
15 benchmarks have a result for both models as of October 21, 2026. Kimi K2.5's coding index rests on 3 independent benchmarks and Nemotron 3.5 Lightning's on 2. Where only one model has a result, the page says so instead of naming a winner.