Claude Haiku 4.5 vs GPT-5.3 Codex — Who Actually Wins? Real Benchmark Data (2026)

head to head

Claude Haiku 4.5 vs GPT-5.3 Codex

2 shared benchmarks

0

wins

0

ties

2

wins

50.7%

OSWorld

64.0%

73.3%

SWE-bench Verified

80.0%