Comparison · prices as of 2026-07-04
GPT-5.1 vs Grok 4
On price alone, GPT-5.1 (OpenAI) runs about 44% cheaper than Grok 4 for a typical chat workload (2K input + 500 output tokens, 1,000 requests/day). Whether that's the right trade depends on the capability gap — pricing below, verify quality on your own evals.
| Spec | GPT-5.1 | Grok 4 |
|---|---|---|
| Input / MTok | $1.25 | $3 |
| Output / MTok | $10 | $15 |
| Context window | 400K | 256K |
| Max output | 128K | 64K |
| Class | frontier | frontier |
| Reference workload / month | $225.00 | $405.00 |
Sources: OpenAI pricing · xAI pricing. Run your own numbers in the cost calculator.