GPT-5.3 Codex vs GPT-4.1

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

GPT-5.3 Codex is clearly ahead on the aggregate, 92 to 43. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.3 Codex's sharpest advantage is in mathematics, where it averages 97.4 against 26.4. The single biggest benchmark swing on the page is AIME 2024, 99 to 26.4.

GPT-5.3 Codex is also the more expensive model on tokens at $2.50 input / $10.00 output per 1M tokens, versus $2.00 input / $8.00 output per 1M tokens for GPT-4.1. GPT-5.3 Codex is the reasoning model in the pair, while GPT-4.1 is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. GPT-4.1 gives you the larger context window at 1M, compared with 400K for GPT-5.3 Codex.

Quick Verdict

Pick GPT-5.3 Codex if you want the stronger benchmark profile. GPT-4.1 only becomes the better choice if you want the cheaper token bill or you need the larger 1M context window.

Knowledge

GPT-5.3 Codex

GPT-5.3 Codex

86.3

GPT-4.1

78.3

99
MMLU
90.2
97
GPQA
66.3
95
SuperGPQA
-
93
OpenBookQA
-
90
MMLU-Pro
-
44
HLE
-

Coding

GPT-5.3 Codex

GPT-5.3 Codex

88.3

GPT-4.1

54.6

95
HumanEval
-
85
SWE-bench Verified
54.6
85
LiveCodeBench
-

Mathematics

GPT-5.3 Codex

GPT-5.3 Codex

97.4

GPT-4.1

26.4

99
AIME 2023
-
99
AIME 2024
26.4
98
AIME 2025
-
95
HMMT Feb 2023
-
97
HMMT Feb 2024
-
96
HMMT Feb 2025
-
96
BRUMO 2025
-
99
MATH-500
-

Reasoning

GPT-5.3 Codex
95
SimpleQA
-
93
MuSR
-
98
BBH
-

Instruction Following

GPT-5.3 Codex

GPT-5.3 Codex

93

GPT-4.1

87.4

93
IFEval
87.4

Multilingual

GPT-5.3 Codex
96
MGSM
-

Frequently Asked Questions

Which is better, GPT-5.3 Codex or GPT-4.1?

GPT-5.3 Codex is ahead overall, 92 to 43. The biggest single separator in this matchup is AIME 2024, where the scores are 99 and 26.4.

Which is better for knowledge tasks, GPT-5.3 Codex or GPT-4.1?

GPT-5.3 Codex has the edge for knowledge tasks in this comparison, averaging 86.3 versus 78.3. Inside this category, GPQA is the benchmark that creates the most daylight between them.

Which is better for coding, GPT-5.3 Codex or GPT-4.1?

GPT-5.3 Codex has the edge for coding in this comparison, averaging 88.3 versus 54.6. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for math, GPT-5.3 Codex or GPT-4.1?

GPT-5.3 Codex has the edge for math in this comparison, averaging 97.4 versus 26.4. Inside this category, AIME 2024 is the benchmark that creates the most daylight between them.

Which is better for instruction following, GPT-5.3 Codex or GPT-4.1?

GPT-5.3 Codex has the edge for instruction following in this comparison, averaging 93 versus 87.4. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Last updated: March 9, 2026

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