Head-to-head comparison across 2benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
DeepSeek V4 Pro (High)
83
GPT-5.5 Pro
100
Verified leaderboard positions: DeepSeek V4 Pro (High) #6 · GPT-5.5 Pro unranked
Pick GPT-5.5 Pro if you want the stronger benchmark profile. DeepSeek V4 Pro (High) only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
Agentic
+20.1 difference
Knowledge
+5.4 difference
DeepSeek V4 Pro (High)
GPT-5.5 Pro
$1.74 / $3.48
$30 / $180
N/A
N/A
N/A
N/A
1M
1M
Pick GPT-5.5 Pro if you want the stronger benchmark profile. DeepSeek V4 Pro (High) only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
GPT-5.5 Pro is clearly ahead on the provisional aggregate, 100 to 83. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.5 Pro's sharpest advantage is in agentic, where it averages 90.1 against 70. The single biggest benchmark swing on the page is HLE, 34.5% to 57.2%. DeepSeek V4 Pro (High) does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.
GPT-5.5 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $1.74 input / $3.48 output per 1M tokens for DeepSeek V4 Pro (High). That is roughly 51.7x on output cost alone.
GPT-5.5 Pro is ahead on BenchLM's provisional leaderboard, 100 to 83. The biggest single separator in this matchup is HLE, where the scores are 34.5% and 57.2%.
DeepSeek V4 Pro (High) has the edge for knowledge tasks in this comparison, averaging 62.6 versus 57.2. Inside this category, HLE is the benchmark that creates the most daylight between them.
GPT-5.5 Pro has the edge for agentic tasks in this comparison, averaging 90.1 versus 70. Inside this category, BrowseComp is the benchmark that creates the most daylight between them.
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