Grok 3 mini vs Grok 4.1 Fast

Grok 3 mini vs Grok 4.1 Fast: Grok 4.1 Fast is cheaper by 61% on average. Grok 3 mini from Azure AI Foundry (131,072-token context, reasoning, tool calls) vs. Grok 4.1 Fast from xAI (2,000,000-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
Azure AI Foundry
$191/mo
Input $0.250/M · Output $1.27/M
xAI
$122/mo
Input $0.200/M · Output $0.500/M
At this workload, Grok 4.1 Fast is 36% cheaper than Grok 3 mini — a savings of $69.70/month ($836/year).
Production recipe — Agent Command Center
strategy: cost-optimized
primary:
  model: grok-4-1-fast
  provider: xai
fallback:
  model: grok-3-mini
  provider: azure-ai-foundry
shadow: { sample_rate: 0.05 }   # mirror 5% of traffic to compare quality live
Grok 3 mini Grok 4.1 Fast
xAI
Input price $0.250/M $0.200/M
Output price $1.27/M $0.500/M
Context window 131,072 2,000,000
Max output 131,072 2,000,000
Function calling
Vision
Audio input
Reasoning
Prompt caching
Structured output
Pricing verified May 12, 2026 May 12, 2026
Cheaper option
~61% cheaper than Grok 3 mini
Larger context
2,000,000 tokens
More capabilities
6 of 6 capability flags advertised