GPT-5.2 Instant vs Gemini 3 Flash

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

GPT-5.2 Instant is clearly ahead on the aggregate, 85 to 62. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.2 Instant's sharpest advantage is in coding, where it averages 75.5 against 40.4. The single biggest benchmark swing on the page is LiveCodeBench, 74 to 36.

GPT-5.2 Instant is also the more expensive model on tokens at $1.50 input / $6.00 output per 1M tokens, versus $0.50 input / $3.00 output per 1M tokens for Gemini 3 Flash. That is roughly 2.0x on output cost alone. GPT-5.2 Instant is the reasoning model in the pair, while Gemini 3 Flash 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. Gemini 3 Flash gives you the larger context window at 1M, compared with 128K for GPT-5.2 Instant.

Quick Verdict

Pick GPT-5.2 Instant if you want the stronger benchmark profile. Gemini 3 Flash only becomes the better choice if you want the cheaper token bill or you need the larger 1M context window.

Agentic

GPT-5.2 Instant

GPT-5.2 Instant

79.6

Gemini 3 Flash

57.5

83
Terminal-Bench 2.0
56
82
BrowseComp
66
74
OSWorld-Verified
53

Coding

GPT-5.2 Instant

GPT-5.2 Instant

75.5

Gemini 3 Flash

40.4

87
HumanEval
62
75
SWE-bench Verified
44
74
LiveCodeBench
36
77
SWE-bench Pro
44

Multimodal & Grounded

GPT-5.2 Instant

GPT-5.2 Instant

93.1

Gemini 3 Flash

79.6

94
MMMU-Pro
80
92
OfficeQA Pro
79

Reasoning

GPT-5.2 Instant

GPT-5.2 Instant

90.9

Gemini 3 Flash

72

95
SimpleQA
67
93
MuSR
65
96
BBH
84
89
LongBench v2
75
84
MRCRv2
76

Knowledge

GPT-5.2 Instant

GPT-5.2 Instant

79.8

Gemini 3 Flash

52.9

98
MMLU
70
97
GPQA
69
95
SuperGPQA
67
93
OpenBookQA
65
88
MMLU-Pro
72
43
HLE
6
91
FrontierScience
65

Instruction Following

GPT-5.2 Instant

GPT-5.2 Instant

95

Gemini 3 Flash

85

95
IFEval
85

Multilingual

GPT-5.2 Instant

GPT-5.2 Instant

94.4

Gemini 3 Flash

80.5

95
MGSM
85
94
MMLU-ProX
78

Mathematics

GPT-5.2 Instant

GPT-5.2 Instant

97.2

Gemini 3 Flash

74

99
AIME 2023
70
99
AIME 2024
72
98
AIME 2025
71
95
HMMT Feb 2023
66
97
HMMT Feb 2024
68
96
HMMT Feb 2025
67
96
BRUMO 2025
69
98
MATH-500
80

Frequently Asked Questions

Which is better, GPT-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant is ahead overall, 85 to 62. The biggest single separator in this matchup is LiveCodeBench, where the scores are 74 and 36.

Which is better for knowledge tasks, GPT-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant has the edge for knowledge tasks in this comparison, averaging 79.8 versus 52.9. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for coding, GPT-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant has the edge for coding in this comparison, averaging 75.5 versus 40.4. Inside this category, LiveCodeBench is the benchmark that creates the most daylight between them.

Which is better for math, GPT-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant has the edge for math in this comparison, averaging 97.2 versus 74. Inside this category, AIME 2023 is the benchmark that creates the most daylight between them.

Which is better for reasoning, GPT-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant has the edge for reasoning in this comparison, averaging 90.9 versus 72. Inside this category, SimpleQA is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant has the edge for agentic tasks in this comparison, averaging 79.6 versus 57.5. 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-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant has the edge for multimodal and grounded tasks in this comparison, averaging 93.1 versus 79.6. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, GPT-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant has the edge for instruction following in this comparison, averaging 95 versus 85. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, GPT-5.2 Instant or Gemini 3 Flash?

GPT-5.2 Instant has the edge for multilingual tasks in this comparison, averaging 94.4 versus 80.5. Inside this category, MMLU-ProX is the benchmark that creates the most daylight between them.

Last updated: March 12, 2026

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