Head-to-head comparison across 5benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
GPT-5.4 Pro
92
GPT-5.5
89
Verified leaderboard positions: GPT-5.4 Pro unranked · GPT-5.5 #2
Pick GPT-5.4 Pro if you want the stronger benchmark profile. GPT-5.5 only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
Agentic
+7.5 difference
Reasoning
+1.7 difference
Knowledge
+17.4 difference
Math
+1.7 difference
Multimodal
+25.0 difference
GPT-5.4 Pro
GPT-5.5
$30 / $180
$5 / $30
74 t/s
N/A
151.79s
N/A
1.05M
1M
Pick GPT-5.4 Pro if you want the stronger benchmark profile. GPT-5.5 only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
GPT-5.4 Pro has the cleaner provisional overall profile here, landing at 92 versus 89. It is a real lead, but still close enough that category-level strengths matter more than the headline number.
GPT-5.4 Pro's sharpest advantage is in multimodal & grounded, where it averages 94 against 69. The single biggest benchmark swing on the page is MMMU-Pro, 94% to 81.2%. GPT-5.5 does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.
GPT-5.4 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $5.00 input / $30.00 output per 1M tokens for GPT-5.5. That is roughly 6.0x on output cost alone. GPT-5.4 Pro gives you the larger context window at 1.05M, compared with 1M for GPT-5.5.
GPT-5.4 Pro is ahead on BenchLM's provisional leaderboard, 92 to 89. The biggest single separator in this matchup is MMMU-Pro, where the scores are 94% and 81.2%.
GPT-5.5 has the edge for knowledge tasks in this comparison, averaging 66.4 versus 49. Inside this category, HLE is the benchmark that creates the most daylight between them.
GPT-5.5 has the edge for math in this comparison, averaging 51.7 versus 50. Inside this category, FrontierMath is the benchmark that creates the most daylight between them.
GPT-5.5 has the edge for reasoning in this comparison, averaging 85 versus 83.3. Inside this category, ARC-AGI-2 is the benchmark that creates the most daylight between them.
GPT-5.4 Pro has the edge for agentic tasks in this comparison, averaging 89.3 versus 81.8. Inside this category, BrowseComp is the benchmark that creates the most daylight between them.
GPT-5.4 Pro has the edge for multimodal and grounded tasks in this comparison, averaging 94 versus 69. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.
For engineers, researchers, and the plain curious — a weekly brief on new models, ranking shifts, and pricing changes.
Free. No spam. Unsubscribe anytime.