Side-by-side comparison of pricing, 12 benchmarks, and generation speed.
| Metric | Grok 4 Fast (Reasoning) | Llama 3.1 Instruct 70B |
|---|---|---|
| Input ($/M tokens) | $0.2 | $0.56 |
| Output ($/M tokens) | $0.5 | $0.56 |
Data from Artificial Analysis API — 12 benchmarks
Grok 4 Fast (Reasoning) is cheaper overall. Its blended price (3:1 input/output ratio) is $0.28/M tokens vs $0.56/M for Llama 3.1 Instruct 70B.
Grok 4 Fast (Reasoning) wins 11 out of 12 benchmarks compared to 1 for Llama 3.1 Instruct 70B. See the detailed benchmark chart above for per-category results.
Grok 4 Fast (Reasoning) generates tokens faster at 120 tok/s vs 31 tok/s. However, Llama 3.1 Instruct 70B has lower time-to-first-token (0.55s vs 4.60s).
Choose based on your priorities: Grok 4 Fast (Reasoning) for lower cost, Grok 4 Fast (Reasoning) for stronger benchmark performance, and Grok 4 Fast (Reasoning) for faster generation. For latency-sensitive apps, check the TTFT comparison above.