Side-by-side benchmark comparison across knowledge, coding, math, and reasoning.
GPT-5.4 Pro is clearly ahead on the aggregate, 94 to 34. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.4 Pro's sharpest advantage is in coding, where it averages 89 against 16. The single biggest benchmark swing on the page is LiveCodeBench, 86 to 11.
GPT-5.4 Pro is the reasoning model in the pair, while GPT-OSS 20B 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. GPT-5.4 Pro gives you the larger context window at 1.05M, compared with 128K for GPT-OSS 20B.
Pick GPT-5.4 Pro if you want the stronger benchmark profile. GPT-OSS 20B only becomes the better choice if you would rather avoid the extra latency and token burn of a reasoning model.
GPT-5.4 Pro
88.8
GPT-OSS 20B
28.2
GPT-5.4 Pro
89
GPT-OSS 20B
16
GPT-5.4 Pro
98
GPT-OSS 20B
33.6
GPT-5.4 Pro
96.7
GPT-OSS 20B
39.3
GPT-5.4 Pro
97
GPT-OSS 20B
67
GPT-5.4 Pro
97
GPT-OSS 20B
61
GPT-5.4 Pro is ahead overall, 94 to 34. The biggest single separator in this matchup is LiveCodeBench, where the scores are 86 and 11.
GPT-5.4 Pro has the edge for knowledge tasks in this comparison, averaging 88.8 versus 28.2. Inside this category, GPQA is the benchmark that creates the most daylight between them.
GPT-5.4 Pro has the edge for coding in this comparison, averaging 89 versus 16. Inside this category, LiveCodeBench is the benchmark that creates the most daylight between them.
GPT-5.4 Pro has the edge for math in this comparison, averaging 98 versus 33.6. Inside this category, HMMT Feb 2023 is the benchmark that creates the most daylight between them.
GPT-5.4 Pro has the edge for reasoning in this comparison, averaging 96.7 versus 39.3. Inside this category, SimpleQA is the benchmark that creates the most daylight between them.
GPT-5.4 Pro has the edge for instruction following in this comparison, averaging 97 versus 67. Inside this category, IFEval is the benchmark that creates the most daylight between them.
GPT-5.4 Pro has the edge for multilingual tasks in this comparison, averaging 97 versus 61. Inside this category, MGSM is the benchmark that creates the most daylight between them.
Get notified when new models drop, benchmark scores change, or the leaderboard shifts. One email per week.
Free. No spam. Unsubscribe anytime. We only store derived location metadata for consent routing.