GPT-5.4 vs Claude Mythos Preview — Who Actually Wins? Real Benchmark Data (2026)

head to head

GPT-5.4 vs Claude Mythos Preview

8 shared benchmarks

0

wins

0

ties

8

wins

82.7%

BrowseComp

86.9%

92.8%

GPQA Diamond

94.6%

36.24%

Humanity's Last Exam

56.8%

75.0%

OSWorld

79.6%

57.7%

SWE-bench Pro

77.8%

77.2%

SWE-bench Verified

93.9%

81.8%

Terminal-Bench 2.0

82.0%

95.2%

USAMO 2026

97.6%