GPT-5.3-Codex-Spark vs Claude 4.1 Opus

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

GPT-5.3-Codex-Spark is clearly ahead on the aggregate, 87 to 64. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.3-Codex-Spark's sharpest advantage is in coding, where it averages 82.3 against 44. The single biggest benchmark swing on the page is LiveCodeBench, 80 to 40.

GPT-5.3-Codex-Spark is the reasoning model in the pair, while Claude 4.1 Opus 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-5.3-Codex-Spark gives you the larger context window at 256K, compared with 200K for Claude 4.1 Opus.

Quick Verdict

Pick GPT-5.3-Codex-Spark if you want the stronger benchmark profile. Claude 4.1 Opus only becomes the better choice if you would rather avoid the extra latency and token burn of a reasoning model.

Agentic

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

85.6

Claude 4.1 Opus

58.7

90
Terminal-Bench 2.0
58
82
BrowseComp
62
83
OSWorld-Verified
57

Coding

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

82.3

Claude 4.1 Opus

44

91
HumanEval
68
80
SWE-bench Verified
48
80
LiveCodeBench
40
85
SWE-bench Pro
47

Multimodal & Grounded

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

88.3

Claude 4.1 Opus

80.7

86
MMMU-Pro
82
91
OfficeQA Pro
79

Reasoning

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

92.7

Claude 4.1 Opus

72.9

94
SimpleQA
74
92
MuSR
72
97
BBH
81
91
LongBench v2
71
92
MRCRv2
71

Knowledge

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

78.3

Claude 4.1 Opus

57.6

97
MMLU
76
95
GPQA
76
93
SuperGPQA
74
91
OpenBookQA
72
88
MMLU-Pro
75
42
HLE
11
88
FrontierScience
68

Instruction Following

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

92

Claude 4.1 Opus

83

92
IFEval
83

Multilingual

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

90.8

Claude 4.1 Opus

81.8

94
MGSM
85
89
MMLU-ProX
80

Mathematics

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

96.7

Claude 4.1 Opus

77.7

98
AIME 2023
76
98
AIME 2024
78
97
AIME 2025
77
94
HMMT Feb 2023
72
96
HMMT Feb 2024
74
95
HMMT Feb 2025
73
95
BRUMO 2025
75
98
MATH-500
81

Frequently Asked Questions

Which is better, GPT-5.3-Codex-Spark or Claude 4.1 Opus?

GPT-5.3-Codex-Spark is ahead overall, 87 to 64. The biggest single separator in this matchup is LiveCodeBench, where the scores are 80 and 40.

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

GPT-5.3-Codex-Spark has the edge for knowledge tasks in this comparison, averaging 78.3 versus 57.6. Inside this category, HLE is the benchmark that creates the most daylight between them.

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

GPT-5.3-Codex-Spark has the edge for coding in this comparison, averaging 82.3 versus 44. Inside this category, LiveCodeBench is the benchmark that creates the most daylight between them.

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

GPT-5.3-Codex-Spark has the edge for math in this comparison, averaging 96.7 versus 77.7. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, GPT-5.3-Codex-Spark or Claude 4.1 Opus?

GPT-5.3-Codex-Spark has the edge for reasoning in this comparison, averaging 92.7 versus 72.9. Inside this category, MRCRv2 is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.3-Codex-Spark or Claude 4.1 Opus?

GPT-5.3-Codex-Spark has the edge for agentic tasks in this comparison, averaging 85.6 versus 58.7. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, GPT-5.3-Codex-Spark or Claude 4.1 Opus?

GPT-5.3-Codex-Spark has the edge for multimodal and grounded tasks in this comparison, averaging 88.3 versus 80.7. 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-Spark or Claude 4.1 Opus?

GPT-5.3-Codex-Spark has the edge for instruction following in this comparison, averaging 92 versus 83. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, GPT-5.3-Codex-Spark or Claude 4.1 Opus?

GPT-5.3-Codex-Spark has the edge for multilingual tasks in this comparison, averaging 90.8 versus 81.8. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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