Grok 4.1 Fast vs Nemotron 3 Nano Omni
Grok 4.1 Fast (2025) and Nemotron 3 Nano Omni (2026) are frontier reasoning models from xAI and NVIDIA AI. Grok 4.1 Fast ships a 2m-token context window, while Nemotron 3 Nano Omni ships a 262k-token context window. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads. It focuses on practical selection signals rather than broad model-family marketing.
Grok 4.1 Fast fits 8x more tokens; pick it for long-context work and Nemotron 3 Nano Omni for tighter calls.
Decision scorecard
Local evidence first| Signal | Grok 4.1 Fast | Nemotron 3 Nano Omni |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | multimodal apps |
| Decision fit | RAG, Agents, and Long context | Long context, Vision, and Classification |
| Context window | 2m | 262k |
| Cheapest output | $0.50/1M tokens | - |
| Provider routes | 2 tracked | 1 tracked |
| Shared benchmarks | 0 shared | 0 shared |
Decision tradeoffs
- Grok 4.1 Fast has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Grok 4.1 Fast has broader tracked provider coverage for fallback and procurement flexibility.
- Grok 4.1 Fast uniquely exposes Vision, Reasoning, and Function calling in local model data.
- Local decision data tags Grok 4.1 Fast for RAG, Agents, and Long context.
- Local decision data tags Nemotron 3 Nano Omni for Long context, Vision, and Classification.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Grok 4.1 Fast
$285
Cheapest tracked route/tier: OpenRouter
Nemotron 3 Nano Omni
Unavailable
No complete token price in local provider data
Cost delta unavailable until both models have sourced input and output token prices.
Switch friction
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- Check replacement coverage for Vision, Reasoning, and Function calling before moving production traffic.
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- Grok 4.1 Fast adds Vision, Reasoning, and Function calling in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-11-19 | 2026-04-28 |
| Context window | 2m | 262k |
| Parameters | — | 30B |
| Architecture | - | MoE + SSM Hybrid |
| License | Proprietary | NVIDIA Open Model |
| Openness | Proprietary | Open weights |
| Commercial use | Commercial use: conditional | Commercial use: permitted |
| Knowledge cutoff | - | - |
Pricing and availability
| Pricing attribute | Grok 4.1 Fast | Nemotron 3 Nano Omni |
|---|---|---|
| Input price | $0.20/1M tokens | - |
| Output price | $0.50/1M tokens | - |
| Providers |
Capabilities
| Capability | Grok 4.1 Fast | Nemotron 3 Nano Omni |
|---|---|---|
| Vision | Yes | No |
| Multimodal | Yes | Yes |
| Reasoning | Yes | No |
| Function calling | Yes | No |
| Tool use | Yes | No |
| Structured outputs | Yes | No |
| Code execution | No | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark scores are currently available for this pair.
Deep dive
The capability footprint differs most on vision: Grok 4.1 Fast, reasoning mode: Grok 4.1 Fast, function calling: Grok 4.1 Fast, tool use: Grok 4.1 Fast, and structured outputs: Grok 4.1 Fast. Both models share multimodal input, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
Pricing coverage is uneven: Grok 4.1 Fast has $0.20/1M input tokens and Nemotron 3 Nano Omni has no token price sourced yet. Provider availability is 2 tracked routes versus 1. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose Grok 4.1 Fast when reasoning depth, larger context windows, and broader provider choice are central to the workload. Choose Nemotron 3 Nano Omni when provider fit are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.
FAQ
Which has a larger context window, Grok 4.1 Fast or Nemotron 3 Nano Omni?
Grok 4.1 Fast supports 2m tokens, while Nemotron 3 Nano Omni supports 262k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Is Grok 4.1 Fast or Nemotron 3 Nano Omni open source?
Grok 4.1 Fast is listed under Proprietary. Nemotron 3 Nano Omni is listed under NVIDIA Open Model. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, Grok 4.1 Fast or Nemotron 3 Nano Omni?
Grok 4.1 Fast has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for multimodal input, Grok 4.1 Fast or Nemotron 3 Nano Omni?
Both Grok 4.1 Fast and Nemotron 3 Nano Omni expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Which is better for reasoning mode, Grok 4.1 Fast or Nemotron 3 Nano Omni?
Grok 4.1 Fast has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run Grok 4.1 Fast and Nemotron 3 Nano Omni?
Grok 4.1 Fast is available on OpenRouter and xAI Console. Nemotron 3 Nano Omni is available on OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.