GPT-5.3-Codex-Spark vs Claude 4.1 Opus Thinking

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 44. 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 21.8. The single biggest benchmark swing on the page is LiveCodeBench, 80 to 15.

GPT-5.3-Codex-Spark gives you the larger context window at 256K, compared with 200K for Claude 4.1 Opus Thinking.

Quick Verdict

Pick GPT-5.3-Codex-Spark if you want the stronger benchmark profile. Claude 4.1 Opus Thinking only becomes the better choice if its workflow or ecosystem matters more than the raw scoreboard.

Agentic

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

85.6

Claude 4.1 Opus Thinking

46.7

90
Terminal-Bench 2.0
45
82
BrowseComp
49
83
OSWorld-Verified
47

Coding

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

82.3

Claude 4.1 Opus Thinking

21.8

91
HumanEval
30
80
SWE-bench Verified
20
80
LiveCodeBench
15
85
SWE-bench Pro
29

Multimodal & Grounded

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

88.3

Claude 4.1 Opus Thinking

59.3

86
MMMU-Pro
62
91
OfficeQA Pro
56

Reasoning

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

92.7

Claude 4.1 Opus Thinking

49.4

94
SimpleQA
36
92
MuSR
34
97
BBH
67
91
LongBench v2
60
92
MRCRv2
60

Knowledge

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

78.3

Claude 4.1 Opus Thinking

34.3

97
MMLU
38
95
GPQA
37
93
SuperGPQA
35
91
OpenBookQA
33
88
MMLU-Pro
53
42
HLE
8
88
FrontierScience
41

Instruction Following

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

92

Claude 4.1 Opus Thinking

66

92
IFEval
66

Multilingual

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

90.8

Claude 4.1 Opus Thinking

58.7

94
MGSM
60
89
MMLU-ProX
58

Mathematics

GPT-5.3-Codex-Spark

GPT-5.3-Codex-Spark

96.7

Claude 4.1 Opus Thinking

48.3

98
AIME 2023
38
98
AIME 2024
40
97
AIME 2025
39
94
HMMT Feb 2023
34
96
HMMT Feb 2024
36
95
HMMT Feb 2025
35
95
BRUMO 2025
37
98
MATH-500
62

Frequently Asked Questions

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

GPT-5.3-Codex-Spark is ahead overall, 87 to 44. The biggest single separator in this matchup is LiveCodeBench, where the scores are 80 and 15.

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

GPT-5.3-Codex-Spark has the edge for knowledge tasks in this comparison, averaging 78.3 versus 34.3. 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 4.1 Opus Thinking?

GPT-5.3-Codex-Spark has the edge for coding in this comparison, averaging 82.3 versus 21.8. 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 Thinking?

GPT-5.3-Codex-Spark has the edge for math in this comparison, averaging 96.7 versus 48.3. 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 Thinking?

GPT-5.3-Codex-Spark has the edge for reasoning in this comparison, averaging 92.7 versus 49.4. 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 4.1 Opus Thinking?

GPT-5.3-Codex-Spark has the edge for agentic tasks in this comparison, averaging 85.6 versus 46.7. 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 Thinking?

GPT-5.3-Codex-Spark has the edge for multimodal and grounded tasks in this comparison, averaging 88.3 versus 59.3. 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 Thinking?

GPT-5.3-Codex-Spark has the edge for instruction following in this comparison, averaging 92 versus 66. 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 Thinking?

GPT-5.3-Codex-Spark has the edge for multilingual tasks in this comparison, averaging 90.8 versus 58.7. Inside this category, MGSM is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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