GPT-5.3 Codex vs Ministral 3 14B (Reasoning)

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

GPT-5.3 Codex is clearly ahead on the aggregate, 89 to 60. 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 coding, where it averages 87.3 against 35. The single biggest benchmark swing on the page is SWE-bench Pro, 90 to 36.

GPT-5.3 Codex is also the more expensive model on tokens at $2.50 input / $10.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Ministral 3 14B (Reasoning). That is roughly Infinityx on output cost alone. GPT-5.3 Codex gives you the larger context window at 400K, compared with 128K for Ministral 3 14B (Reasoning).

Quick Verdict

Pick GPT-5.3 Codex if you want the stronger benchmark profile. Ministral 3 14B (Reasoning) only becomes the better choice if you want the cheaper token bill.

Agentic

GPT-5.3 Codex

GPT-5.3 Codex

88.1

Ministral 3 14B (Reasoning)

58.5

90
Terminal-Bench 2.0
60
88
BrowseComp
61
86
OSWorld-Verified
55

Coding

GPT-5.3 Codex

GPT-5.3 Codex

87.3

Ministral 3 14B (Reasoning)

35

95
HumanEval
62
85
SWE-bench Verified
39
85
LiveCodeBench
33
90
SWE-bench Pro
36

Multimodal & Grounded

GPT-5.3 Codex

GPT-5.3 Codex

91.3

Ministral 3 14B (Reasoning)

71.5

89
MMMU-Pro
71
94
OfficeQA Pro
72

Reasoning

GPT-5.3 Codex

GPT-5.3 Codex

93.7

Ministral 3 14B (Reasoning)

69.2

95
SimpleQA
70
93
MuSR
70
98
BBH
80
92
LongBench v2
66
93
MRCRv2
66

Knowledge

GPT-5.3 Codex

GPT-5.3 Codex

80.3

Ministral 3 14B (Reasoning)

52.1

99
MMLU
71
97
GPQA
70
95
SuperGPQA
68
93
OpenBookQA
66
90
MMLU-Pro
69
44
HLE
7
90
FrontierScience
62

Instruction Following

GPT-5.3 Codex

GPT-5.3 Codex

93

Ministral 3 14B (Reasoning)

81

93
IFEval
81

Multilingual

GPT-5.3 Codex

GPT-5.3 Codex

92.8

Ministral 3 14B (Reasoning)

77.8

96
MGSM
81
91
MMLU-ProX
76

Mathematics

GPT-5.3 Codex

GPT-5.3 Codex

97.7

Ministral 3 14B (Reasoning)

75.2

99
AIME 2023
73
99
AIME 2024
75
98
AIME 2025
74
95
HMMT Feb 2023
69
97
HMMT Feb 2024
71
96
HMMT Feb 2025
70
96
BRUMO 2025
72
99
MATH-500
79

Frequently Asked Questions

Which is better, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex is ahead overall, 89 to 60. The biggest single separator in this matchup is SWE-bench Pro, where the scores are 90 and 36.

Which is better for knowledge tasks, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex has the edge for knowledge tasks in this comparison, averaging 80.3 versus 52.1. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for coding, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex has the edge for coding in this comparison, averaging 87.3 versus 35. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.

Which is better for math, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex has the edge for math in this comparison, averaging 97.7 versus 75.2. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex has the edge for reasoning in this comparison, averaging 93.7 versus 69.2. Inside this category, MRCRv2 is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex has the edge for agentic tasks in this comparison, averaging 88.1 versus 58.5. Inside this category, OSWorld-Verified is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex has the edge for multimodal and grounded tasks in this comparison, averaging 91.3 versus 71.5. Inside this category, OfficeQA Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex has the edge for instruction following in this comparison, averaging 93 versus 81. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, GPT-5.3 Codex or Ministral 3 14B (Reasoning)?

GPT-5.3 Codex has the edge for multilingual tasks in this comparison, averaging 92.8 versus 77.8. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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