GPT 5.3 Codex

Release Date: 2/24/2026

Accuracy (Average)

66.99%

Latency (Average)

1801.56s

Avg. Cost (In/Out)

1.75 / 14

Context Window

400k

Max Output Tokens

128k

Input Modality

Hyperparameter settings
Default Provider : OpenAI

Temperature

Default

Top P

Default

Top K

Default

Max Output Tokens

128,000

Reasoning Effort

xhigh

Benchmarks

Accuracy

Rankings

0.0%

± 4.71
2/ 25

0.0%

± 7.81
3/ 50

0.0%

± 0.97
3/ 102

0.0%

± 1.85
4/ 40

0.0%

± 5.12
2/ 51
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