DeepSeek-R1-Lite Preview and GPT-5.6 Sol don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. DeepSeek-R1-Lite Preview shipped 583 days before GPT-5.6 Sol, so benchmark comparisons should account for the intervening progress.

DeepSeek-R1-Lite Preview is open weight, while GPT-5.6 Sol is proprietary.

Direct benchmark comparisons are unavailable — DeepSeek-R1-Lite Preview and GPT-5.6 Sol don't publish scores on any of the same benchmarks.