OpenAI GPT-4.1 nano: fastest and most cost-efficient GPT-4.1 model, 1M token context, fine-tuning and predicted outputs supported, no reasoning step.
Capabilities, design details, and architectural traits
GPT 4.1 nano is OpenAI's officially designated fastest and cheapest model in the GPT-4.1 family. It carries the same 1M token context window as GPT 4.1 and GPT 4.1 mini, but runs at a Very fast speed tier with an Average intelligence rating - the lowest latency point in the 4.1 generation. It produces output without a reasoning step.
| Trait | Detail |
|---|---|
| Speed and cost tier | Rated Very fast - the highest speed and lowest cost position in the entire GPT-4.1 family |
| Context window | 1,047,576 tokens (1M) at very-fast speed - no other GPT-4.1 family member combines this context size with this speed tier |
| Fine-tuning | Supported, including supervised fine-tuning and direct preference optimization |
| Predicted outputs | Supported - allows supplying an expected completion to accelerate responses |
OpenAI positions GPT 4.1 nano specifically for tasks that demand low latency, with its 1M context window making it suited for high-volume, latency-sensitive workloads that still need large-context handling. The combination of fine-tuning support and very-fast speed at the nano tier was not available in the prior generation's smallest model.
Independent evaluations · Artificial Analysis
Evaluate specifications, pricing, and independent benchmark indices
| Model Details | |||
|---|---|---|---|
| General Info | |||
| Provider | OpenAI | Anthropic | Anthropic |
| Release Date | April 14, 2025 | July 24, 2026 | June 9, 2026 |
| Knowledge Cutoff | Jun 2024 | May 2026 | - |
| Context & Limits | |||
| Context Window | 1.0M Best Context Window | 1M | 1M |
| Pricing (per 1M tokens) | |||
| Input Pricing | $0.10 Best Input Pricing | $5 | $10 |
| Output Pricing | $0.40 Best Output Pricing | $25 | $50 |
| Modalities | |||
| Inputs | imagetextfile | textimage | textimagefile |
| Outputs | text | text | text |
| Benchmarks (0-100) | |||
| Intelligence Index | 9.6 | 63.1 Best Intelligence Index | 62.1 |
| Coding Index | 11.1 | 78.0 Best Coding Index | 76.5 |
| Agentic Index | 1.2 | 59.2 Best Agentic Index | 56.6 |
Graduate-level reasoning and expert Q&A evaluation.
Extremely difficult logical reasoning and knowledge.
Logical reasoning over long context windows.
Independent evaluation data provided by Artificial Analysis. To view the latest benchmarks and full details, visit their official site.
