Head-to-head comparison across 5benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
GPT-5.2
83
GPT-5.5
89
Verified leaderboard positions: GPT-5.2 unranked · GPT-5.5 #2
Pick GPT-5.5 if you want the stronger benchmark profile. GPT-5.2 only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
Agentic
+26.6 difference
Coding
+6.1 difference
Reasoning
+32.1 difference
Knowledge
+26.0 difference
Multimodal
+10.5 difference
GPT-5.2
GPT-5.5
$1.75 / $14
$5 / $30
73 t/s
N/A
130.34s
N/A
400K
1M
Pick GPT-5.5 if you want the stronger benchmark profile. GPT-5.2 only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
GPT-5.5 is clearly ahead on the provisional aggregate, 89 to 83. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.5's sharpest advantage is in reasoning, where it averages 85 against 52.9. The single biggest benchmark swing on the page is ARC-AGI-2, 52.9% to 85%. GPT-5.2 does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.
GPT-5.5 is also the more expensive model on tokens at $5.00 input / $30.00 output per 1M tokens, versus $1.75 input / $14.00 output per 1M tokens for GPT-5.2. That is roughly 2.1x on output cost alone. GPT-5.5 gives you the larger context window at 1M, compared with 400K for GPT-5.2.
GPT-5.5 is ahead on BenchLM's provisional leaderboard, 89 to 83. The biggest single separator in this matchup is ARC-AGI-2, where the scores are 52.9% and 85%.
GPT-5.2 has the edge for knowledge tasks in this comparison, averaging 92.4 versus 66.4. Inside this category, GPQA is the benchmark that creates the most daylight between them.
GPT-5.2 has the edge for coding in this comparison, averaging 64.7 versus 58.6. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.
GPT-5.5 has the edge for reasoning in this comparison, averaging 85 versus 52.9. Inside this category, ARC-AGI-2 is the benchmark that creates the most daylight between them.
GPT-5.5 has the edge for agentic tasks in this comparison, averaging 81.8 versus 55.2. Inside this category, OSWorld-Verified is the benchmark that creates the most daylight between them.
GPT-5.2 has the edge for multimodal and grounded tasks in this comparison, averaging 79.5 versus 69. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.
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