Grok 4.3 vs Nemotron 3 Nano Omni
Grok 4.3 (2026) and Nemotron 3 Nano Omni (2026) are frontier reasoning models from xAI and NVIDIA AI. Grok 4.3 ships a 1M-token context window, while Nemotron 3 Nano Omni ships a 262K-token context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing. The goal is to make the tradeoff clear before deeper testing.
Grok 4.3 is safer overall; choose Nemotron 3 Nano Omni when provider fit matters.
Decision scorecard
Local evidence first| Signal | Grok 4.3 | Nemotron 3 Nano Omni |
|---|---|---|
| Decision fit | RAG, Agents, and Long context | Long context and Vision |
| Context window | 1M | 262K |
| Cheapest output | $2.5/1M tokens | - |
| Provider routes | 2 tracked | 1 tracked |
| Shared benchmarks | 0 rows | 0 rows |
Decision tradeoffs
- Grok 4.3 has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Grok 4.3 has broader tracked provider coverage for fallback and procurement flexibility.
- Grok 4.3 uniquely exposes Vision, Reasoning, and Function calling in local model data.
- Local decision data tags Grok 4.3 for RAG, Agents, and Long context.
- Local decision data tags Nemotron 3 Nano Omni for Long context and Vision.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output prices on this page.
Grok 4.3
$1,625
Cheapest tracked route: xAI Console
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 4.3 adds Vision, Reasoning, and Function calling in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-05-05 | 2026-04-28 |
| Context window | 1M | 262K |
| Parameters | ~0.5T | 30B |
| Architecture | - | Hybrid Mamba-Transformer MoE |
| License | Proprietary | Open Source |
| Knowledge cutoff | - | - |
Pricing and availability
| Pricing attribute | Grok 4.3 | Nemotron 3 Nano Omni |
|---|---|---|
| Input price | $1.25/1M tokens | - |
| Output price | $2.5/1M tokens | - |
| Providers |
Capabilities
| Capability | Grok 4.3 | 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 |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on vision: Grok 4.3, reasoning mode: Grok 4.3, function calling: Grok 4.3, tool use: Grok 4.3, and structured outputs: Grok 4.3. 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 4.3 has $1.25/1M 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 4.3 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 4.3 or Nemotron 3 Nano Omni?
Grok 4.3 supports 1M 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 4.3 or Nemotron 3 Nano Omni open source?
Grok 4.3 is listed under Proprietary. Nemotron 3 Nano Omni is listed under Open Source. 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 4.3 or Nemotron 3 Nano Omni?
Grok 4.3 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. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, Grok 4.3 or Nemotron 3 Nano Omni?
Both Grok 4.3 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 4.3 or Nemotron 3 Nano Omni?
Grok 4.3 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 4.3 and Nemotron 3 Nano Omni?
Grok 4.3 is available on xAI Console and OpenRouter. Nemotron 3 Nano Omni is available on OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Continue comparing
Last reviewed: 2026-05-14. Data sourced from public model cards and provider documentation.