Grok 4.6 vs Nemotron 3.5 Lightning
Grok 4.6 leads Nemotron 3.5 Lightning on coding, 65.7 to 22.6 on the Vibe Coding Index, and Nemotron 3.5 Lightning costs 40.8x less per output token ($0.147 vs $6.00 per million). Updated October 22, 2026; 20 benchmarks have a result for both.
Grok 4.6 or Nemotron 3.5 Lightning: which to pick
Pick Grok 4.6 for coding: it scores 65.7 on the Vibe Coding Index against 22.6 for Nemotron 3.5 Lightning.
Pick Nemotron 3.5 Lightning for output tokens 40.8x cheaper ($0.147 vs $6.00 per million) and a lower cost per solved task ($0.06 against $0.82).
- Shared results
- 20
- Grok 4.6 only
- 103
- Nemotron 3.5 Lightning only
- 0
- 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
Grok 4.6
Grok 4.6 scores 65.7 against 22.6.
6 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
Grok 4.6
Grok 4.6 leads, 44.3 against 12.9.
Same board, both measured
Agentic work
AA Agentic Index
Grok 4.6
Grok 4.6 leads, 53.0 against 3.5.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only Grok 4.6 has a GPQA Diamond result, 94.7%.
Directional only
Knowledge
MMLU Pro
No call
Only Grok 4.6 has a MMLU Pro result, 89.4%.
Directional only
Web design
Design Arena: websites
No call
Only Grok 4.6 has a Design Arena: websites result, 1289.
Directional only
Long documents
Listed context window
Grok 4.6
Grok 4.6 takes 500K tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Nemotron 3.5 Lightning
Grok 4.6 $0.0050, Nemotron 3.5 Lightning $0.0001 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Nemotron 3.5 Lightning
Grok 4.6 $0.82, Nemotron 3.5 Lightning $0.06.
Published attempt cost and pass rate
At a glance
- Coding index
- Grok 4.6 65.7 from 6 benchmarks, Nemotron 3.5 Lightning 22.6 from 2 benchmarks.
- Widest category
- General, 51.5 points apart on average over 2 shared benchmarks.
- Widest single gap
- MedScribe (Vals AI): Grok 4.6 86.5% against Nemotron 3.5 Lightning 4.3%, 82.3 points apart on a 0 to 100 scale.
- Output price
- Grok 4.6 $6.00 against Nemotron 3.5 Lightning $0.147 per million output tokens, 40.8x apart.
- Context window
- Grok 4.6 takes 500K tokens, Nemotron 3.5 Lightning 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 | Grok 4.6 | Bars | Nemotron 3.5 Lightning | Ties |
|---|---|---|---|---|
| Coding | 9 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 5 | 0 | ||
| Reasoning | 2 | 0 | ||
| Knowledge | 1 | 0 | ||
| General | 2 | 0 | ||
| All shared boards | 20 | 0 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index90
| Benchmark | Grok 4.6 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| LiveBench coding | 89.1% | Not measured | Only Grok 4.6 measured |
| LMArena WebDev | 1617 | Not measured | Only Grok 4.6 measured |
| AA Coding Index | 76.8 | 26.8 | Grok 4.6 |
| LiveCodeBench (Vals AI) | 88.2% | Not measured | Only Grok 4.6 measured |
| SWE-bench Verified (Vals AI) | 95.6% | 52.8% | Grok 4.6 |
| Terminal-Bench 4 (Vals AI) | 17.2% | Not measured | Only Grok 4.6 measured |
| Vibe Code Bench (Vals AI) | 76.2% | 0.0% | Grok 4.6 |
| Code migration (Vals AI) | 44.6% | 3.0% | Grok 4.6 |
| ProgramBench (Vals AI) | 1.0% | 0.0% | Grok 4.6 |
| IOI (Vals AI) | 47.6% | Not measured | Only Grok 4.6 measured |
| Terminal-Bench 2.1 (Vals AI) | 78.3% | 10.9% | Grok 4.6 |
| Vibe Code Bench 1-100 (Vals AI) | 14.8% | Not measured | Only Grok 4.6 measured |
| SkillsBench (Vals AI) | 55.8% | Not measured | Only Grok 4.6 measured |
| CyberBench (Vals AI) | 67.7% | 29.5% | Grok 4.6 |
| SciCode | 56.5% | 32.1% | Grok 4.6 |
| FrontierCode | 48.0% | Not measured | Only Grok 4.6 measured |
| FrontierSWE | 25.3% | Not measured | Only Grok 4.6 measured |
| WeirdML | 67.3% | Not measured | Only Grok 4.6 measured |
| ALE-Bench | 1508.1 | 769.2 | Grok 4.6 |
| LMArena Text: coding | 1466 | Not measured | Only Grok 4.6 measured |
| LMArena Text: software and IT | 1457 | Not measured | Only Grok 4.6 measured |
| LMArena WebDev: React | 1631 | Not measured | Only Grok 4.6 measured |
| LMArena WebDev: HTML | 1597 | Not measured | Only Grok 4.6 measured |
| LMArena WebDev: from an image | 1603 | Not measured | Only Grok 4.6 measured |
| Neither model has a result on the other 15 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Grok 4.6 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| AA Intelligence Index | 44.3 | 12.9 | Grok 4.6 |
| Epoch Capabilities Index | 156.6 | Not measured | Only Grok 4.6 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Grok 4.6 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| AA Agentic Index | 53.0 | 3.5 | Grok 4.6 |
| Design Arena: agents building web apps | 1248 | Not measured | Only Grok 4.6 measured |
| Design Arena: agents building full-stack apps | 1264 | Not measured | Only Grok 4.6 measured |
| Design Arena: agents building mobile apps | 1234 | Not measured | Only Grok 4.6 measured |
| Design Arena: agents building Android apps | 1291 | Not measured | Only Grok 4.6 measured |
| Design Arena: agents building Godot games | 1276 | Not measured | Only Grok 4.6 measured |
| Design Arena: agents building games | 1209 | Not measured | Only Grok 4.6 measured |
| Design Arena: HTML slides | 1250 | Not measured | Only Grok 4.6 measured |
| Design Arena: PowerPoint slides | 1237 | Not measured | Only Grok 4.6 measured |
| LiveBench research | 84.5% | Not measured | Only Grok 4.6 measured |
| LiveBench browser | 64.0% | Not measured | Only Grok 4.6 measured |
| LiveBench long agentic | 40.7% | Not measured | Only Grok 4.6 measured |
| Finance Agent (Vals AI) | 53.7% | 18.5% | Grok 4.6 |
| Tax Agent Bench (Vals AI) | 33.1% | 2.6% | Grok 4.6 |
| Legal Research Bench (Vals AI) | 48.1% | 2.9% | Grok 4.6 |
| Excel Modeling Benchmark (Vals AI) | 62.7% | 17.0% | Grok 4.6 |
| BioMysteryBench (Vals AI) | 72.2% | Not measured | Only Grok 4.6 measured |
| Terminal-Bench-Science (Vals AI) | 11.4% | Not measured | Only Grok 4.6 measured |
| Vals Science Index | 38.1% | Not measured | Only Grok 4.6 measured |
| Time Horizon Index (Vals AI) | 5.8% | Not measured | Only Grok 4.6 measured |
| APEX-Agents | 65.3% | Not measured | Only Grok 4.6 measured |
| Vending-Bench 2 | $9,047 | Not measured | Only Grok 4.6 measured |
| Neither model has a result on the other 19 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Grok 4.6 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| GPQA Diamond | 94.7% | Not measured | Only Grok 4.6 measured |
| LiveBench reasoning | 91.2% | Not measured | Only Grok 4.6 measured |
| MysteryMechanism (Vals AI) | 30.6% | Not measured | Only Grok 4.6 measured |
| GPQA Diamond (Artificial Analysis run) | 94.9% | 74.3% | Grok 4.6 |
| Humanity's Last Exam (Artificial Analysis run) | 44.1% | 10.6% | Grok 4.6 |
| GPQA Diamond (Epoch AI run) | 94.0% | Not measured | Only Grok 4.6 measured |
| ARC-AGI | 87.5% | Not measured | Only Grok 4.6 measured |
| ARC-AGI-2 | 67.1% | Not measured | Only Grok 4.6 measured |
| SimpleBench | 75.9% | Not measured | Only Grok 4.6 measured |
| Chess puzzles | 33.0% | Not measured | Only Grok 4.6 measured |
| Mystery game puzzles | 34.0% | Not measured | Only Grok 4.6 measured |
| EBR-bench | 30.5% | Not measured | Only Grok 4.6 measured |
| LMArena Text: hard prompts | 1448 | Not measured | Only Grok 4.6 measured |
| LMArena Text: expert | 1469 | Not measured | Only Grok 4.6 measured |
| LMArena Text: hard prompts in English | 1445 | Not measured | Only Grok 4.6 measured |
| LMArena Vision: diagrams | 1285 | Not measured | Only Grok 4.6 measured |
| LMArena Vision: homework | 1283 | Not measured | Only Grok 4.6 measured |
| Neither model has a result on the other 5 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index6 boards, none shared
| Benchmark | Grok 4.6 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| OTIS Mock AIME | 99.2% | Not measured | Only Grok 4.6 measured |
| FrontierMath, tiers 1 to 3 | 66.0% | Not measured | Only Grok 4.6 measured |
| FrontierMath, tier 4 | 31.7% | Not measured | Only Grok 4.6 measured |
| ProofBench | 51.0% | Not measured | Only Grok 4.6 measured |
| LMArena Text: math | 1417 | Not measured | Only Grok 4.6 measured |
| LMArena Text: mathematical work | 1464 | Not measured | Only Grok 4.6 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 | Grok 4.6 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| MMLU Pro | 89.4% | Not measured | Only Grok 4.6 measured |
| LegalBench (Vals AI) | 86.3% | Not measured | Only Grok 4.6 measured |
| CorpFin (Vals AI) | 66.2% | 54.2% | Grok 4.6 |
| TaxEval (Vals AI) | 71.1% | Not measured | Only Grok 4.6 measured |
| MortgageTax (Vals AI) | 64.2% | Not measured | Only Grok 4.6 measured |
| MedCode (Vals AI) | 44.7% | Not measured | Only Grok 4.6 measured |
| SimpleQA Verified | 49.3% | Not measured | Only Grok 4.6 measured |
| LMArena Text: science | 1437 | Not measured | Only Grok 4.6 measured |
| LMArena Text: medicine and healthcare | 1420 | Not measured | Only Grok 4.6 measured |
| LMArena Text: legal and government | 1429 | Not measured | Only Grok 4.6 measured |
| LMArena Text: business and finance | 1416 | Not measured | Only Grok 4.6 measured |
| Neither model has a result on the other 7 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared
| Benchmark | Grok 4.6 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| Design Arena: websites | 1289 | Not measured | Only Grok 4.6 measured |
| Design Arena: UI components | 1294 | Not measured | Only Grok 4.6 measured |
| Design Arena: game dev | 1296 | Not measured | Only Grok 4.6 measured |
| Design Arena: data viz | 1282 | Not measured | Only Grok 4.6 measured |
| Design Arena: 3D | 1277 | Not measured | Only Grok 4.6 measured |
| Design Arena: all code categories | 1292 | Not measured | Only Grok 4.6 measured |
| Design Arena: SVG | 1240 | Not measured | Only Grok 4.6 measured |
| Design Arena: ASCII art | 1279 | Not measured | Only Grok 4.6 measured |
| LiveBench design | 79.8% | Not measured | Only Grok 4.6 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Grok 4.6 | Nemotron 3.5 Lightning | Leader |
|---|---|---|---|
| LiveBench data analysis | 75.3% | Not measured | Only Grok 4.6 measured |
| Public Benefits Bench (Vals AI) | 66.8% | Not measured | Only Grok 4.6 measured |
| SAGE (Vals AI) | 28.9% | Not measured | Only Grok 4.6 measured |
| MedScribe (Vals AI) | 86.5% | 4.3% | Grok 4.6 |
| Long context reasoning (AA-LCR) | 81.0% | 60.3% | Grok 4.6 |
| DTBench | 97.3% | Not measured | Only Grok 4.6 measured |
| LMCA | 48.5% | Not measured | Only Grok 4.6 measured |
| Furniture assembly | 40.0% | Not measured | Only Grok 4.6 measured |
| LMArena Text | 1429 | Not measured | Only Grok 4.6 measured |
| LMArena Text: instruction following | 1431 | Not measured | Only Grok 4.6 measured |
| LMArena Text: creative writing | 1426 | Not measured | Only Grok 4.6 measured |
| LMArena Vision | 1263 | Not measured | Only Grok 4.6 measured |
| LMArena Text: English | 1433 | Not measured | Only Grok 4.6 measured |
| LMArena Text: non-English | 1420 | Not measured | Only Grok 4.6 measured |
| LMArena Text: Chinese | 1476 | Not measured | Only Grok 4.6 measured |
| LMArena Text: German | 1426 | Not measured | Only Grok 4.6 measured |
| LMArena Text: Japanese | 1378 | Not measured | Only Grok 4.6 measured |
| LMArena Text: Korean | 1391 | Not measured | Only Grok 4.6 measured |
| LMArena Text: French | 1455 | Not measured | Only Grok 4.6 measured |
| LMArena Text: Spanish | 1414 | Not measured | Only Grok 4.6 measured |
| LMArena Text: Russian | 1421 | Not measured | Only Grok 4.6 measured |
| LMArena Text: Polish | 1430 | Not measured | Only Grok 4.6 measured |
| LMArena Text: multi-turn | 1425 | Not measured | Only Grok 4.6 measured |
| LMArena Text: longer queries | 1456 | Not measured | Only Grok 4.6 measured |
| LMArena Text: writing and language | 1429 | Not measured | Only Grok 4.6 measured |
| LMArena Text: entertainment and media | 1421 | Not measured | Only Grok 4.6 measured |
| LMArena Vision: English | 1270 | Not measured | Only Grok 4.6 measured |
| LMArena Vision: Chinese | 1289 | Not measured | Only Grok 4.6 measured |
| LMArena Vision: reading text | 1272 | Not measured | Only Grok 4.6 measured |
| LMArena Vision: humor | 1270 | Not measured | Only Grok 4.6 measured |
| LMArena Vision: creative writing | 1262 | Not measured | Only Grok 4.6 measured |
| LMArena Document | 1452 | Not measured | Only Grok 4.6 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 | Grok 4.6 | 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 | SpaceXAI Grok 4.6 | NVIDIA Nemotron 3.5 Lightning |
|---|---|---|
| Maker | xAI | NVIDIA |
| Weights | No public weights listed | Open weights |
| Released | August 12, 2026 | August 11, 2026 |
| Context window | 500K | 262K |
| Input $/Mtok | $2.00 | $0.0534 |
| Output $/Mtok | $6.00 | $0.147 |
| Coding index | 65.7 | 22.6 |
| Independent measurements behind it | 6 | 2 |
| Cost per solved task | $0.82 | $0.06 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Grok 4.6 better than Nemotron 3.5 Lightning for coding?
Pick Grok 4.6 for coding: it scores 65.7 on the Vibe Coding Index against 22.6 for Nemotron 3.5 Lightning. Pick Nemotron 3.5 Lightning for output tokens 40.8x cheaper ($0.147 vs $6.00 per million) and a lower cost per solved task ($0.06 against $0.82).
Which is cheaper, Grok 4.6 or Nemotron 3.5 Lightning?
Grok 4.6 costs $2.00 per million input tokens and $6.00 per million output tokens; Nemotron 3.5 Lightning costs $0.0534 and $0.147. Per solved SWE-bench Verified task, Grok 4.6 costs $0.82 and Nemotron 3.5 Lightning $0.06.
Which has the bigger context window, Grok 4.6 or Nemotron 3.5 Lightning?
Grok 4.6, with 500K tokens against 262K.
How many benchmarks is the Grok 4.6 vs Nemotron 3.5 Lightning comparison based on?
20 benchmarks have a result for both models as of October 22, 2026. Grok 4.6's coding index rests on 6 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.