GPT-5.5 vs DeepSeek V4 Pro — Who Actually Wins? Real Benchmark Data (2026)

head to head

GPT-5.5 vs DeepSeek V4 Pro

9 shared benchmarks

8

wins

0

ties

1

wins

38.5%

APEX-Agents

38.3%

84.4%

BrowseComp

83.4%

93.5%

GPQA Diamond

90.1%

41.4%

Humanity's Last Exam

37.7%

82.8%

MCP-Atlas

73.6%

74.0%

MRCR v2

83.5%

58.6%

SWE-bench Pro

55.4%

82.7%

Terminal-Bench 2.0

67.9%

55.6%

Toolathlon

51.8%