Head-to-head comparison across 3benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
GPT-5.4 Pro
92
GPT-5.5 Pro
100
Pick GPT-5.5 Pro if you want the stronger benchmark profile. GPT-5.4 Pro only becomes the better choice if you need the larger 1.05M context window.
Agentic
+0.8 difference
Knowledge
+8.2 difference
Math
+2.4 difference
GPT-5.4 Pro
GPT-5.5 Pro
$30 / $180
$30 / $180
74 t/s
N/A
151.79s
N/A
1.05M
1M
Pick GPT-5.5 Pro if you want the stronger benchmark profile. GPT-5.4 Pro only becomes the better choice if you need the larger 1.05M context window.
GPT-5.5 Pro is clearly ahead on the provisional aggregate, 100 to 92. 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 knowledge, where it averages 57.2 against 49. The single biggest benchmark swing on the page is FrontierMath, 50% to 52.4%.
GPT-5.4 Pro gives you the larger context window at 1.05M, compared with 1M for GPT-5.5 Pro.
GPT-5.5 Pro is ahead on BenchLM's provisional leaderboard, 100 to 92. The biggest single separator in this matchup is FrontierMath, where the scores are 50% and 52.4%.
GPT-5.5 Pro has the edge for knowledge tasks in this comparison, averaging 57.2 versus 49. Inside this category, HLE is the benchmark that creates the most daylight between them.
GPT-5.5 Pro has the edge for math in this comparison, averaging 52.4 versus 50. Inside this category, FrontierMath 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 89.3. Inside this category, BrowseComp 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.