claude-sonnet-4-6 vs gpt-5-chat Benchmark Comparison

Direct benchmark comparison between claude-sonnet-4-6 and gpt-5-chat based on LMArena Elo and the latest 2026 API pricing.

Direct Technical & Pricing Comparison

Frontier Model	LMArena Elo	API Cost (1M)	Throughput
claude-sonnet-4-6	1461	$0.000003	45
gpt-5-chat	1426	$0.00000125	96

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

Comparison Summary: claude-sonnet-4-6 is the more capable model in this pair, leading by 35 Elo points. However, neither model is currently Pareto-optimal. Developers looking for peak efficiency should investigate gpt-5.2-chat-latest-20260210, which offers a superior benchmark-to-price ratio.