GPT-5.3-Codex-Spark vs Claude 3 Haiku

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 49. 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 19.3. The single biggest benchmark swing on the page is SWE-bench Pro, 85 to 19.

GPT-5.3-Codex-Spark is the reasoning model in the pair, while Claude 3 Haiku 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 3 Haiku.

Quick Verdict

Pick GPT-5.3-Codex-Spark if you want the stronger benchmark profile. Claude 3 Haiku 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 3 Haiku

44

90
Terminal-Bench 2.0
40
82
BrowseComp
53
83
OSWorld-Verified
42

Coding

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

82.3

Claude 3 Haiku

19.3

91
HumanEval
48
80
SWE-bench Verified
17
80
LiveCodeBench
20
85
SWE-bench Pro
19

Multimodal & Grounded

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

88.3

Claude 3 Haiku

68.7

86
MMMU-Pro
70
91
OfficeQA Pro
67

Reasoning

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

92.7

Claude 3 Haiku

59.6

94
SimpleQA
54
92
MuSR
52
97
BBH
74
91
LongBench v2
63
92
MRCRv2
63

Knowledge

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

78.3

Claude 3 Haiku

42.8

97
MMLU
56
95
GPQA
56
93
SuperGPQA
54
91
OpenBookQA
52
88
MMLU-Pro
63
42
HLE
2
88
FrontierScience
50

Instruction Following

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

92

Claude 3 Haiku

76

92
IFEval
76

Multilingual

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

90.8

Claude 3 Haiku

71.1

94
MGSM
73
89
MMLU-ProX
70

Mathematics

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

96.7

Claude 3 Haiku

62.2

98
AIME 2023
56
98
AIME 2024
58
97
AIME 2025
57
94
HMMT Feb 2023
52
96
HMMT Feb 2024
54
95
HMMT Feb 2025
53
95
BRUMO 2025
55
98
MATH-500
71

Frequently Asked Questions

Which is better, GPT-5.3-Codex-Spark or Claude 3 Haiku?

GPT-5.3-Codex-Spark is ahead overall, 87 to 49. The biggest single separator in this matchup is SWE-bench Pro, where the scores are 85 and 19.

Which is better for knowledge tasks, GPT-5.3-Codex-Spark or Claude 3 Haiku?

GPT-5.3-Codex-Spark has the edge for knowledge tasks in this comparison, averaging 78.3 versus 42.8. Inside this category, MMLU is the benchmark that creates the most daylight between them.

Which is better for coding, GPT-5.3-Codex-Spark or Claude 3 Haiku?

GPT-5.3-Codex-Spark has the edge for coding in this comparison, averaging 82.3 versus 19.3. 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-Spark or Claude 3 Haiku?

GPT-5.3-Codex-Spark has the edge for math in this comparison, averaging 96.7 versus 62.2. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, GPT-5.3-Codex-Spark or Claude 3 Haiku?

GPT-5.3-Codex-Spark has the edge for reasoning in this comparison, averaging 92.7 versus 59.6. 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 3 Haiku?

GPT-5.3-Codex-Spark has the edge for agentic tasks in this comparison, averaging 85.6 versus 44. 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 3 Haiku?

GPT-5.3-Codex-Spark has the edge for multimodal and grounded tasks in this comparison, averaging 88.3 versus 68.7. 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 3 Haiku?

GPT-5.3-Codex-Spark has the edge for instruction following in this comparison, averaging 92 versus 76. 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 3 Haiku?

GPT-5.3-Codex-Spark has the edge for multilingual tasks in this comparison, averaging 90.8 versus 71.1. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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