Nemotron 3 Ultra vs Step 3.5 Flash
Nemotron 3 Ultra leads Step 3.5 Flash on the Artificial Analysis Intelligence Index, 22.9 to 17.0, and Step 3.5 Flash costs 8.0x less per output token ($0.30 vs $2.40 per million). Updated October 22, 2026; 34 benchmarks have a result for both.
Nemotron 3 Ultra or Step 3.5 Flash: which to pick
Only Nemotron 3 Ultra has a coding score, 30.0 on the Vibe Coding Index; Step 3.5 Flash has none, so the two cannot be ranked on coding.
Pick Step 3.5 Flash for output tokens 8.0x cheaper ($0.30 vs $2.40 per million) and work measured by τ²-Bench Telecom or LMArena Text: Polish, where it leads.
- Shared results
- 34
- Nemotron 3 Ultra only
- 37
- Step 3.5 Flash only
- 2
- Like-for-like categories
- 7 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
No call
Only Nemotron 3 Ultra has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
Nemotron 3 Ultra
Nemotron 3 Ultra leads, 22.9 against 17.0.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Nemotron 3 Ultra has a AA Agentic Index result, 20.1.
Directional only
Reasoning
GPQA Diamond
No call
Only Nemotron 3 Ultra has a GPQA Diamond result, 86.1%.
Directional only
Knowledge
MMLU Pro
No call
Only Nemotron 3 Ultra has a MMLU Pro result, 85.8%.
Directional only
Web design
Design Arena: websites
No call
Only Nemotron 3 Ultra has a Design Arena: websites result, 1145.
Directional only
Long documents
Listed context window
No call
Both take 262K tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Step 3.5 Flash
Nemotron 3 Ultra $0.0018, Step 3.5 Flash $0.0003 per turn.
List prices
At a glance
- Coding index
- Nemotron 3 Ultra 30.0 from 3 benchmarks, Step 3.5 Flash not benchmarked.
- Widest category
- Agentic work, 11.1 points apart on average over 1 shared benchmark.
- Widest single gap
- Long context reasoning (AA-LCR): Nemotron 3 Ultra 79.3% against Step 3.5 Flash 63.0%, 16.3 points apart on a 0 to 100 scale.
- Output price
- Nemotron 3 Ultra $2.40 against Step 3.5 Flash $0.30 per million output tokens, 8.0x 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 | Nemotron 3 Ultra | Bars | Step 3.5 Flash | Ties |
|---|---|---|---|---|
| Coding | 3 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 0 | 1 | ||
| Reasoning | 5 | 0 | ||
| Math | 2 | 0 | ||
| Knowledge | 4 | 0 | ||
| General | 17 | 1 | ||
| All shared boards | 32 | 2 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index30
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | Leader |
|---|---|---|---|
| AA Coding Index | 49.3 | Not measured | Only Nemotron 3 Ultra measured |
| LiveCodeBench (Vals AI) | 86.0% | Not measured | Only Nemotron 3 Ultra measured |
| SWE-bench Verified (Vals AI) | 69.0% | Not measured | Only Nemotron 3 Ultra measured |
| Vibe Code Bench (Vals AI) | 7.6% | Not measured | Only Nemotron 3 Ultra measured |
| Code migration (Vals AI) | 4.9% | Not measured | Only Nemotron 3 Ultra measured |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only Nemotron 3 Ultra measured |
| Terminal-Bench 2.1 (Vals AI) | 50.9% | Not measured | Only Nemotron 3 Ultra measured |
| SciCode | 40.3% | Not measured | Only Nemotron 3 Ultra measured |
| Terminal-Bench Hard (Artificial Analysis run) | 36.4% | 32.6% | Nemotron 3 Ultra |
| FrontierCode | 13.6% | Not measured | Only Nemotron 3 Ultra measured |
| WeirdML | 43.5% | Not measured | Only Nemotron 3 Ultra measured |
| LMArena Text: coding | 1468 | 1436 | Nemotron 3 Ultra |
| LMArena Text: software and IT | 1468 | 1434 | Nemotron 3 Ultra |
| Neither model has a result on the other 30 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | Leader |
|---|---|---|---|
| AA Intelligence Index | 22.9 | 17.0 | Nemotron 3 Ultra |
| Epoch Capabilities Index | 146.0 | Not measured | Only Nemotron 3 Ultra measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | Leader |
|---|---|---|---|
| AA Agentic Index | 20.1 | Not measured | Only Nemotron 3 Ultra measured |
| Finance Agent (Vals AI) | 37.7% | Not measured | Only Nemotron 3 Ultra measured |
| Legal Research Bench (Vals AI) | 15.4% | Not measured | Only Nemotron 3 Ultra measured |
| Excel Modeling Benchmark (Vals AI) | 31.7% | Not measured | Only Nemotron 3 Ultra measured |
| τ²-Bench Telecom | 83.3% | 94.4% | Step 3.5 Flash |
| APEX-Agents | 22.7% | Not measured | Only Nemotron 3 Ultra measured |
| MCP Atlas | 63.1% | Not measured | Only Nemotron 3 Ultra measured |
| Neither model has a result on the other 35 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | Leader |
|---|---|---|---|
| GPQA Diamond | 86.1% | Not measured | Only Nemotron 3 Ultra measured |
| GPQA Diamond (Artificial Analysis run) | 86.7% | 83.1% | Nemotron 3 Ultra |
| Humanity's Last Exam (Artificial Analysis run) | 28.4% | 24.5% | Nemotron 3 Ultra |
| GPQA Diamond (Epoch AI run) | 85.4% | Not measured | Only Nemotron 3 Ultra measured |
| Mystery game puzzles | 20.0% | Not measured | Only Nemotron 3 Ultra measured |
| LMArena Text: hard prompts | 1452 | 1411 | Nemotron 3 Ultra |
| LMArena Text: expert | 1472 | 1421 | Nemotron 3 Ultra |
| LMArena Text: hard prompts in English | 1453 | 1421 | Nemotron 3 Ultra |
| Neither model has a result on the other 15 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | Leader |
|---|---|---|---|
| OTIS Mock AIME | 86.7% | Not measured | Only Nemotron 3 Ultra measured |
| ProofBench | 2.0% | Not measured | Only Nemotron 3 Ultra measured |
| LMArena Text: math | 1457 | 1408 | Nemotron 3 Ultra |
| LMArena Text: mathematical work | 1461 | 1421 | Nemotron 3 Ultra |
| MathArena | Not measured | 19.4% | Only Step 3.5 Flash measured |
| Neither model has a result on the other 9 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | Leader |
|---|---|---|---|
| MMLU Pro | 85.8% | Not measured | Only Nemotron 3 Ultra measured |
| LegalBench (Vals AI) | 82.1% | Not measured | Only Nemotron 3 Ultra measured |
| CorpFin (Vals AI) | 65.5% | Not measured | Only Nemotron 3 Ultra measured |
| TaxEval (Vals AI) | 73.1% | Not measured | Only Nemotron 3 Ultra measured |
| MedCode (Vals AI) | 38.6% | Not measured | Only Nemotron 3 Ultra measured |
| LMArena Text: science | 1465 | 1415 | Nemotron 3 Ultra |
| LMArena Text: medicine and healthcare | 1456 | 1408 | Nemotron 3 Ultra |
| LMArena Text: legal and government | 1452 | 1408 | Nemotron 3 Ultra |
| LMArena Text: business and finance | 1434 | 1394 | Nemotron 3 Ultra |
| Neither model has a result on the other 11 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | Leader |
|---|---|---|---|
| Design Arena: websites | 1145 | Not measured | Only Nemotron 3 Ultra measured |
| Design Arena: UI components | 1135 | Not measured | Only Nemotron 3 Ultra measured |
| Design Arena: game dev | 1138 | Not measured | Only Nemotron 3 Ultra measured |
| Design Arena: data viz | 1141 | Not measured | Only Nemotron 3 Ultra measured |
| Design Arena: 3D | 1131 | Not measured | Only Nemotron 3 Ultra measured |
| Design Arena: all code categories | 1146 | Not measured | Only Nemotron 3 Ultra measured |
| Design Arena: SVG | 1069 | Not measured | Only Nemotron 3 Ultra measured |
| Design Arena: ASCII art | 1100 | Not measured | Only Nemotron 3 Ultra measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index171
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | Leader |
|---|---|---|---|
| IFBench | 81.4% | 66.5% | Nemotron 3 Ultra |
| Long context reasoning (AA-LCR) | 79.3% | 63.0% | Nemotron 3 Ultra |
| DTBench | 90.1% | Not measured | Only Nemotron 3 Ultra measured |
| LMCA | 36.9% | Not measured | Only Nemotron 3 Ultra measured |
| LMArena Text | 1445 | 1403 | Nemotron 3 Ultra |
| LMArena Text: instruction following | 1418 | 1385 | Nemotron 3 Ultra |
| LMArena Text: creative writing | 1399 | 1357 | Nemotron 3 Ultra |
| LMArena Text: English | 1455 | 1417 | Nemotron 3 Ultra |
| LMArena Text: non-English | 1427 | 1385 | Nemotron 3 Ultra |
| LMArena Text: Chinese | 1497 | 1446 | Nemotron 3 Ultra |
| LMArena Text: German | 1472 | 1405 | Nemotron 3 Ultra |
| LMArena Text: Japanese | Not measured | 1353 | Only Step 3.5 Flash measured |
| LMArena Text: Korean | 1384 | 1351 | Nemotron 3 Ultra |
| LMArena Text: French | 1472 | 1421 | Nemotron 3 Ultra |
| LMArena Text: Spanish | 1455 | 1419 | Nemotron 3 Ultra |
| LMArena Text: Russian | 1417 | 1385 | Nemotron 3 Ultra |
| LMArena Text: Polish | 1385 | 1389 | Step 3.5 Flash |
| LMArena Text: multi-turn | 1411 | 1404 | Nemotron 3 Ultra |
| LMArena Text: longer queries | 1437 | 1402 | Nemotron 3 Ultra |
| LMArena Text: writing and language | 1406 | 1372 | Nemotron 3 Ultra |
| LMArena Text: entertainment and media | 1397 | 1360 | Nemotron 3 Ultra |
| Neither model has a result on the other 27 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Nemotron 3 Ultra | Step 3.5 Flash | 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
Step 3.5 Flash costs less
Repository review
50K input + 3K output tokens
Step 3.5 Flash costs less
Agent loop
200K input + 10K output tokens
Step 3.5 Flash 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 | NVIDIA Nemotron 3 Ultra | StepFun Step 3.5 Flash |
|---|---|---|
| Maker | NVIDIA | StepFun |
| Weights | Open weights | Open weights |
| Released | June 4, 2026 | January 29, 2026 |
| Context window | 262K | 262K |
| Input $/Mtok | $0.60 | $0.10 |
| Output $/Mtok | $2.40 | $0.30 |
| Coding index | 30.0 | Not benchmarked |
| Independent measurements behind it | 3 | 0 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Nemotron 3 Ultra better than Step 3.5 Flash for coding?
Only Nemotron 3 Ultra has a coding score, 30.0 on the Vibe Coding Index; Step 3.5 Flash has none, so the two cannot be ranked on coding. Pick Step 3.5 Flash for output tokens 8.0x cheaper ($0.30 vs $2.40 per million) and work measured by τ²-Bench Telecom or LMArena Text: Polish, where it leads.
Which is cheaper, Nemotron 3 Ultra or Step 3.5 Flash?
Nemotron 3 Ultra costs $0.60 per million input tokens and $2.40 per million output tokens; Step 3.5 Flash costs $0.10 and $0.30. Cost per solved task is known for neither of them.
Which has the bigger context window, Nemotron 3 Ultra or Step 3.5 Flash?
Neither: both take 262K tokens.
How many benchmarks is the Nemotron 3 Ultra vs Step 3.5 Flash comparison based on?
34 benchmarks have a result for both models as of October 22, 2026. Nemotron 3 Ultra's coding index rests on 3 independent benchmarks and Step 3.5 Flash's on 0. Where only one model has a result, the page says so instead of naming a winner.