GPT-5.1 vs Grok 4.20 0309
OpenAI vs xAI — benchmarks, pricing, and capabilities side by side.
- •GPT-5.1 has the higher intelligence index (89 vs 88.5)
- •GPT-5.1 is cheaper ($1.25 vs $2.00 per 1M input)
- •GPT-5.1 is faster
| GPT-5.1 | Grok 4.20 0309 | |
|---|---|---|
| Intelligence index | 89 | 88.5 |
| Developer | OpenAI | xAI |
| Type | LLM | LLM |
| Access | API only | — |
| Context window | 400,000 tokens | — |
| Input price | $1.25 / 1M | $2.00 / 1M |
| Output price | $10.00 / 1M | $6.00 / 1M |
| Speed | 115 tok/s | 97 tok/s |
| Released | November 12, 2025 | March 10, 2026 |
| Parameters | — | — |
| Input modalities | Text, Image | — |
| Output modalities | Text | — |
Shared benchmarks
GPT-5.1
Grok 4.20 0309
GPQA Diamond
88.1
88.5
Humanity’s Last Exam
26.5
30