Comparison · prices as of 2026-07-04
Claude Opus 4.5 vs Grok 4 Fast
On price alone, Grok 4 Fast (xAI) runs about 97% cheaper than Claude Opus 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 Opus 4.5 | Grok 4 Fast |
|---|---|---|
| Input / MTok | $5 | $0.20 |
| Output / MTok | $25 | $0.50 |
| Context window | 200K | 2M |
| Max output | 64K | 30K |
| Class | frontier | fast |
| Reference workload / month | $675.00 | $19.50 |
Sources: Anthropic pricing · xAI pricing. Run your own numbers in the cost calculator.