Grok 4.1 Fast vs Grok 4.3
Grok 4.1 Fast vs Grok 4.3: Grok 4.1 Fast is cheaper by 84% on average. Grok 4.1 Fast from xAI (2,000,000-token context, reasoning, tool calls) vs. Grok 4.3 from xAI (1,000,000-token context, reasoning, tool calls). Use Agent Command Center to A/B both in shadow mode and pick the winner per workload.
Side-by-side cost
Live workload comparison
Same workload run through both models. The cheaper one is highlighted.
3,000
02,000,000
400
0200,000
5,000
01,000,000
At this workload, Grok 4.1 Fast is 83% cheaper than Grok 4.3 — a savings of $601/month ($7,214/year).
Production recipe — Agent Command Center
strategy: cost-optimized
primary:
model: grok-4-1-fast
provider: xai
fallback:
model: grok-4-3
provider: xai
shadow: { sample_rate: 0.05 } # mirror 5% of traffic to compare quality live| Grok 4.1 Fast | Grok 4.3 | |
|---|---|---|
| Input price | $0.200/M | $1.25/M |
| Output price | $0.500/M | $2.50/M |
| Context window | 2,000,000 | 1,000,000 |
| Max output | 2,000,000 | 1,000,000 |
| Function calling | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio input | ✓ | — |
| Reasoning | ✓ | ✓ |
| Prompt caching | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Pricing verified | May 12, 2026 | May 12, 2026 |
Benchmark comparison
Side-by-side public benchmark scores. Greener bar = winner.