GPT-4o vs GPT-5.1
Both have similar output pricing, while GPT-5.1 offers a larger context window. Choose GPT-4o or GPT-5.1 based on the trade-off between cost, context, and the benchmarks that matter for your use case.
| Spec | GPT-4o | GPT-5.1 |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Input / 1M tokens | $2.50 | $1.25 |
| Output / 1M tokens | $10.00 | $10.00 |
| Context window | 128K | 400K |
| Parameters | — | — |
| Open weights | No | No |
| Released | May 2024 | Nov 2025 |
| SWE-bench Verified score | 38.8 | 66.0 |
| SWE-bench Multimodal score | 30.4 | — |
| LMArena (Chatbot Arena) Elo score | 1300 | 1443 |
| LMArena Vision Elo score | 1137 | 1250 |
| GPQA Diamond score | 49.2 | 87.6 |
| FrontierMath score | 0.3 | 31.0 |
| Epoch Capabilities Index score | 129 | 150 |
| LiveBench score | — | 72.6 |
| LMArena WebDev Elo score | — | 1395 |
FAQ
Is GPT-4o or GPT-5.1 cheaper?
GPT-4o and GPT-5.1 have comparable output pricing.
Which has the larger context window, GPT-4o or GPT-5.1?
GPT-5.1 has the larger context window (400K tokens).
Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.