gpt-5.1 vs grok-4.20-multi-agent-beta-0309 Benchmark Comparison

Direct benchmark comparison between gpt-5.1 and grok-4.20-multi-agent-beta-0309 based on LMArena Elo and the latest 2026 API pricing.

Direct Technical & Pricing Comparison

Frontier Model	LMArena Elo	API Cost (1M)	Throughput
gpt-5.1	1439	$0.00000125	73
grok-4.20-multi-agent-beta-0309	1476	$0.000002	531

*These models represent the Pareto Frontier (optimal cost-to-performance).*

Comparison Summary: grok-4.20-multi-agent-beta-0309 is the more capable model in this pair, leading by 37 Elo points.