GPT-5.3-Codex-Spark vs Claude 4 Sonnet

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 42.9. The single biggest benchmark swing on the page is LiveCodeBench, 80 to 36.

GPT-5.3-Codex-Spark is the reasoning model in the pair, while Claude 4 Sonnet 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 Sonnet.

Quick Verdict

Pick GPT-5.3-Codex-Spark if you want the stronger benchmark profile. Claude 4 Sonnet 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 Sonnet

57.9

90
Terminal-Bench 2.0
56
82
BrowseComp
62
83
OSWorld-Verified
57

Coding

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

82.3

Claude 4 Sonnet

42.9

91
HumanEval
65
80
SWE-bench Verified
51
80
LiveCodeBench
36
85
SWE-bench Pro
48

Multimodal & Grounded

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

88.3

Claude 4 Sonnet

79.7

86
MMMU-Pro
81
91
OfficeQA Pro
78

Reasoning

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

92.7

Claude 4 Sonnet

71.8

94
SimpleQA
71
92
MuSR
69
97
BBH
82
91
LongBench v2
71
92
MRCRv2
72

Knowledge

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

78.3

Claude 4 Sonnet

56.8

97
MMLU
73
95
GPQA
73
93
SuperGPQA
71
91
OpenBookQA
69
88
MMLU-Pro
75
42
HLE
12
88
FrontierScience
67

Instruction Following

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

92

Claude 4 Sonnet

83

92
IFEval
83

Multilingual

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

90.8

Claude 4 Sonnet

82.1

94
MGSM
84
89
MMLU-ProX
81

Mathematics

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

96.7

Claude 4 Sonnet

76.1

98
AIME 2023
73
98
AIME 2024
75
97
AIME 2025
74
94
HMMT Feb 2023
69
96
HMMT Feb 2024
71
95
HMMT Feb 2025
70
95
BRUMO 2025
72
98
MATH-500
81

Frequently Asked Questions

Which is better, GPT-5.3-Codex-Spark or Claude 4 Sonnet?

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 36.

Which is better for knowledge tasks, GPT-5.3-Codex-Spark or Claude 4 Sonnet?

GPT-5.3-Codex-Spark has the edge for knowledge tasks in this comparison, averaging 78.3 versus 56.8. 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 Sonnet?

GPT-5.3-Codex-Spark has the edge for coding in this comparison, averaging 82.3 versus 42.9. 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 Sonnet?

GPT-5.3-Codex-Spark has the edge for math in this comparison, averaging 96.7 versus 76.1. 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 Sonnet?

GPT-5.3-Codex-Spark has the edge for reasoning in this comparison, averaging 92.7 versus 71.8. Inside this category, SimpleQA is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.3-Codex-Spark or Claude 4 Sonnet?

GPT-5.3-Codex-Spark has the edge for agentic tasks in this comparison, averaging 85.6 versus 57.9. 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 Sonnet?

GPT-5.3-Codex-Spark has the edge for multimodal and grounded tasks in this comparison, averaging 88.3 versus 79.7. 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 Sonnet?

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 Sonnet?

GPT-5.3-Codex-Spark has the edge for multilingual tasks in this comparison, averaging 90.8 versus 82.1. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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