GPT-5.1-Codex vs Nemotron 3 Ultra
Detailed technical comparison between GPT-5.1-Codex (OpenAI) and Nemotron 3 Ultra (Nvidia). Review live API token pricing, context window capabilities, time-to-first-token latency, and verified benchmark scores side-by-side.
Comparison Snapshot
Nemotron 3 Ultra
512,288 tokensTie
Equal CapabilityTie
Equal SpeedNemotron 3 Ultra
$0.50 / MTokGPT-5.1-Codex
GPT-5.1-Codex is a specialized version of GPT-5.1 optimized for software engineering and coding workflows. It is designed for both interactive development sessions and long, independent execution of complex engineering tasks....
Nemotron 3 Ultra
NVIDIA Nemotron 3 Ultra is an open frontier-reasoning and orchestration model from NVIDIA, with 55B active parameters out of 550B total (MoE). Built on a hybrid Transformer-Mamba mixture-of-experts architecture, it...
Technical Specifications
🏆 = Superior Spec| Specification | GPT-5.1-Codex | Nemotron 3 Ultra |
|---|---|---|
| Provider | OpenAI | Nvidia |
| Context Window | 400,000 tokens | 512,288 tokens🏆 |
| Agent Suitability | N/A | N/A |
| Time to First Token (TTFT) | N/A | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | stable | beta |
| API Available | Yes | Yes |
| Released Date | 2025-11-13 | 2026-06-04 |
API Pricing Comparison
Input Price per Million Tokens
GPT-5.1-Codex
$1.25
Nemotron 3 Ultra
$0.50
Output Price per Million Tokens
GPT-5.1-Codex
$10.00
Nemotron 3 Ultra
$2.20
💡 Cost Ratio: Nemotron 3 Ultra is 2.5x cheaper per input token than GPT-5.1-Codex.
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Run side-by-side prompt benchmarks in our dynamic multi-model Sandbox. Compare execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Standardized Scores (0–100%)Scores show verified raw accuracy percentages across standardized AI evaluation suites. Higher bars indicate superior performance in that domain.
GPT-5.1-Codex Quirks & Gotchas
No developer gotchas reported.
Nemotron 3 Ultra Quirks & Gotchas
No developer gotchas reported.
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