Comparison · prices as of 2026-07-04
GPT-5 mini vs Grok 4 Fast
On price alone, Grok 4 Fast (xAI) runs about 57% cheaper than GPT-5 mini 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 mini | Grok 4 Fast |
|---|---|---|
| Input / MTok | $0.25 | $0.20 |
| Output / MTok | $2 | $0.50 |
| Context window | 400K | 2M |
| Max output | 128K | 30K |
| Class | workhorse | fast |
| Reference workload / month | $45.00 | $19.50 |
Sources: OpenAI pricing · xAI pricing. Run your own numbers in the cost calculator.