deepseek-v4-flash-thinking vs gpt-5.1 Benchmark Comparison

Direct benchmark comparison between deepseek-v4-flash-thinking and gpt-5.1 based on LMArena Elo and the latest 2026 API pricing.

Direct Technical & Pricing Comparison

Frontier Model	LMArena Elo	API Cost (1M)	Throughput
deepseek-v4-flash-thinking	1439	$1.12e-7	55
gpt-5.1	1439	$0.00000125	89

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

Comparison Summary: These models are highly competitive, with a negligible Elo gap of only 0 points. The choice between them should be driven by specific API features or provider preference. Specifically, deepseek-v4-flash-thinking is currently on the Pareto line, suggesting it offers better systemic value for its performance tier.