GPT-5.5 vs DeepSeek V4 Pro: Is 34× the Price Worth It for Coding?
GPT-5.5 costs $30/1M output. DeepSeek V4 Pro costs $0.87. That's 34× cheaper — but the SWE-bench Pro gap is just 3.2 points (58.6% vs 55.4%). On LiveCodeBench, DeepSeek leads at 93.5%. When does GPT-5.5 justify its premium? Full data-driven coding comparison.
· CodingFleet