Side-by-side comparison of pricing, 12 benchmarks, and generation speed.
| Metric | Nemotron 3 Nano Omni 30B A3B Reasoning | Step 3.5 Flash 2603 |
|---|---|---|
| Input ($/M tokens) | $0.07 | $0.1 |
| Output ($/M tokens) | $0.3 | $0.3 |
Verdict. Nemotron 3 Nano Omni 30B A3B Reasoning and Step 3.5 Flash 2603 split the benchmark comparison evenly at 1–1. The tiebreaker here is price, speed, and what you actually run them on.
Pricing. Both models sit in the budget bracket for output-token pricing. At 1.0× the per-million-token cost, Step 3.5 Flash 2603 is meaningfully cheaper if your traffic is output-heavy (long completions, document generation, agent loops). Step 3.5 Flash 2603 makes more sense when output volume is low and absolute reasoning quality justifies the premium.
Strengths. Nemotron 3 Nano Omni 30B A3B Reasoning is strongest on Intelligence Index (15.0), Coding Index (13.8). Step 3.5 Flash 2603 leads on Intelligence Index (26.5).
Speed. On throughput, Nemotron 3 Nano Omni 30B A3B Reasoning generates tokens at 328 tok/s versus 205 tok/s — about 38% faster. On time-to-first-token, Step 3.5 Flash 2603 responds in 1060ms vs 1090ms, which matters most for chat-style UIs.
Provider. NVIDIA and StepFun sell to overlapping but distinct developer audiences: NVIDIA tends to ship frontier reasoning models with premium positioning, while StepFun often prices more aggressively. Your existing vendor relationships, billing, and SLA preferences may matter as much as the raw numbers above.
Workload cost. Workload scenarios (per million requests at 30M input + 15M output tokens): Nemotron 3 Nano Omni 30B A3B Reasoning costs $6.60 ($79/year); Step 3.5 Flash 2603 costs $7.50 ($90/year). At a smaller 5M-input/2M-output scale (single-developer tool or prototype): Nemotron 3 Nano Omni 30B A3B Reasoning ≈ $0.95/run, Step 3.5 Flash 2603 ≈ $1.10/run. At agent/realtime scale (200M input / 100M output per million requests): Nemotron 3 Nano Omni 30B A3B Reasoning ≈ $44/run, Step 3.5 Flash 2603 ≈ $50/run. Nemotron 3 Nano Omni 30B A3B Reasoning becomes more attractive at higher volume — the absolute per-token pricing difference compounds when you ship at scale.
Recommendation. Both models have legitimate use cases — the right answer depends on whether you are optimizing for benchmark ceiling, latency, or unit cost. Start with the cheaper / faster model, evaluate against your specific task, and only switch if the upgrade shows a meaningful lift.
Head-to-head deltas
Data from Artificial Analysis API — 12 benchmarks
Nemotron 3 Nano Omni 30B A3B Reasoning is cheaper overall. Its blended price (3:1 input/output ratio) is $0.13/M tokens vs $0.15/M for Step 3.5 Flash 2603.
It's a tie — both models win 1 benchmarks each across 12 evaluated categories. See the detailed benchmark chart above for per-category results.
Nemotron 3 Nano Omni 30B A3B Reasoning generates tokens faster at 328 tok/s vs 205 tok/s. However, Step 3.5 Flash 2603 has lower time-to-first-token (1.06s vs 1.09s).
Choose based on your priorities: Nemotron 3 Nano Omni 30B A3B Reasoning for lower cost, both perform similarly on benchmarks, and Nemotron 3 Nano Omni 30B A3B Reasoning for faster generation. For latency-sensitive apps, check the TTFT comparison above.