benchlm.ai

GPT-5.3 Codex vs Grok 4

Side-by-side benchmark comparison across knowledge, coding, math, and reasoning.

Quick Verdict

GPT-5.3 Codex wins overall with a score of 85 vs 69 (16 point difference).GPT-5.3 Codex wins 4 out of 4 categories.

GPT-5.3 Codex

CreatorOpenAI
TypeProprietary
Context400K
Score85

Grok 4

CreatorxAI
TypeProprietary
Context128K
Score69

Knowledge

GPT-5.3 Codex

GPT-5.3 Codex

96

Grok 4

84.8

99
MMLU
87
97
GPQA
86
95
SuperGPQA
84
93
OpenBookQA
82

Coding

GPT-5.3 Codex

GPT-5.3 Codex

95

Grok 4

79

95
HumanEval
79

Mathematics

GPT-5.3 Codex

GPT-5.3 Codex

97.1

Grok 4

86.6

99
AIME 2023
87
99
AIME 2024
89
98
AIME 2025
88
95
HMMT Feb 2023
84
97
HMMT Feb 2024
86
96
HMMT Feb 2025
85
96
BRUMO 2025
87

Reasoning

GPT-5.3 Codex

GPT-5.3 Codex

94

Grok 4

82

95
SimpleQA
83
93
MuSR
81

Frequently Asked Questions

Which is better, GPT-5.3 Codex or Grok 4?

GPT-5.3 Codex scores higher overall with 85 vs 69, a difference of 16 points across all benchmarks.

Which is better for knowledge tasks, GPT-5.3 Codex or Grok 4?

GPT-5.3 Codex leads in knowledge tasks with an average score of 96 vs 84.8.

Which is better for coding, GPT-5.3 Codex or Grok 4?

GPT-5.3 Codex leads in coding with an average score of 95 vs 79.

Which is better for math, GPT-5.3 Codex or Grok 4?

GPT-5.3 Codex leads in math with an average score of 97.1 vs 86.6.

Which is better for reasoning, GPT-5.3 Codex or Grok 4?

GPT-5.3 Codex leads in reasoning with an average score of 94 vs 82.

Related Comparisons

GPT-5.3 Codex vs GPT-5.4GPT-5.3 Codex vs Gemini 3.1 ProGPT-5.3 Codex vs Claude Opus 4.6GPT-5.3 Codex vs Grok 4.1GPT-5.3 Codex vs GPT-5.2GPT-5.3 Codex vs GPT-5.2-Codex