GPT 5.1 vs Grok 3
GPT 5.1 vs Grok 3: GPT 5.1 is cheaper by 58% on average. GPT 5.1 from Azure OpenAI (272,000-token context, reasoning, tool calls) vs. Grok 3 from xAI (131,072-token context, 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
0272,000
400
0131,072
5,000
01,000,000
At this workload, GPT 5.1 is 48% cheaper than Grok 3 — a savings of $1,103/month ($13,240/year).
Production recipe — Agent Command Center
strategy: cost-optimized
primary:
model: gpt-5-1
provider: azure-openai
fallback:
model: grok-3
provider: xai
shadow: { sample_rate: 0.05 } # mirror 5% of traffic to compare quality live| GPT 5.1 | Grok 3 | |
|---|---|---|
| Input price | $1.25/M | $3.00/M |
| Output price | $10.00/M | $15.00/M |
| Context window | 272,000 | 131,072 |
| Max output | 128,000 | 131,072 |
| 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.
Chatbot Arena ELOgeneral
GPT 5.1
1,455
Grok 3
1,402
GPQA Diamondreasoning⚠ different settings
GPT 5.1
88.1%
Grok 3
75.4%