Comparison · prices as of 2026-07-04
Claude Sonnet 4.5 vs Grok 4 Fast
On price alone, Grok 4 Fast (xAI) runs about 95% cheaper than Claude Sonnet 4.5 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 | Claude Sonnet 4.5 | Grok 4 Fast |
|---|---|---|
| Input / MTok | $3 | $0.20 |
| Output / MTok | $15 | $0.50 |
| Context window | 200K | 2M |
| Max output | 64K | 30K |
| Class | workhorse | fast |
| Reference workload / month | $405.00 | $19.50 |
Sources: Anthropic pricing · xAI pricing. Run your own numbers in the cost calculator.