GPT-5.5 Pro is the stronger all-rounder.GPT-5.4 is cheaper.
Scores updated · 12 tests both models report · How we compare
Where each one wins
Tests won in each of the four areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
Agents and facts rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
GPT-5.4 costs 92% less for the same work.
The biggest differences
The tests each model wins by the widest margin, up to three each. Scores are out of 100.
Where GPT-5.5 Pro pulls ahead
- Extremely hard research-level math problemsFrontierMath Tier 4+29.1points ahead
- Short factual questions, answered correctlySimpleQA Verified+19.4points ahead
- Very hard expert questions across many subjectsHumanity's Last Exam+13.5points ahead
Where GPT-5.4 pulls ahead
No clear win on a test scored out of 100.
Every test, side by side
All 12 tests both models report. The winning score is in its model's colour; marks a score checked independently.
ReasoningGPT-5.5 Pro
- Humanity's Last ExamGPT-5.5 Pro by 13.543.757.2+13.5
- ARC-AGI-2GPT-5.5 Pro by 10.973.384.2+10.9
- CritPtGPT-5.5 Pro by 7.223.430.6+7.2
MathGPT-5.5 Pro
- FrontierMath Tier 4GPT-5.5 Pro by 29.14978+29.1
- FrontierMath Tiers 1-3 (v2)GPT-5.5 Pro by 9.178.687.7+9.1
Other results5 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- frontiermath_tier_4_v1GPT-5.5 Pro by 12.527.139.6+12.5
- FrontierMath (overall)GPT-5.4 by 847.639.6+8
- DNA sequence design for transcription factor bindingGPT-5.5 Pro by 3.712.816.5+3.7
- Hard-negative protein binding predictionGPT-5.4 by 3.53.50+3.5
- ARC-AGI-1GPT-5.5 Pro by 1.393.795+1.3
Questions people ask
Which is better, GPT-5.4 or GPT-5.5 Pro?
GPT-5.5 Pro wins all four areas where both have results: agents, reasoning, facts and math. GPT-5.4 wins none, but costs 92% less.
Which is cheaper?
GPT-5.4 costs $2.50 per million input tokens and $15.00 per million output tokens; GPT-5.5 Pro costs $30.00 and $180.00. That makes GPT-5.4 about 92% cheaper for the same work.
How do you compare the two?
We use the 12 benchmark tests both models have published scores on. The verdict counts the 7 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 5 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.