gemini-3.1-flash-lite-preview vs grok-4.20-beta-0309-reasoning Benchmark Comparison

Direct benchmark comparison between gemini-3.1-flash-lite-preview and grok-4.20-beta-0309-reasoning based on LMArena Elo and the latest 2026 API pricing.

Direct Technical & Pricing Comparison

Frontier Model	LMArena Elo	API Cost (1M)	Throughput
gemini-3.1-flash-lite-preview	1438	$2.5e-7	78
grok-4.20-beta-0309-reasoning	1480	$0.000002	132

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

Comparison Summary: grok-4.20-beta-0309-reasoning is the more capable model in this pair, leading by 42 Elo points.