The two are evenly matched.Gemini 2.5 Pro is better at facts; o3-pro at following instructions.
Scores updated · 10 tests both models report · How we compare
Where each one wins
Tests won in each of the three 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.
Facts and following instructions 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.
Gemini 2.5 Pro costs 89% 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 Gemini 2.5 Pro pulls ahead
No clear win on a test scored out of 100.
Where o3-pro pulls ahead
- Keeps track of context across a multi-turn chatMulti-Challenge+8.8points ahead
Every test, side by side
All 10 tests both models report. The winning score is in its model's colour; marks a score checked independently.
FactsGemini 2.5 Pro
- Vectara HHEM hallucination ratelower is betterGemini 2.5 Pro by 16.3723.3+16.3
Following instructionso3-pro
- Multi-Challengeo3-pro by 8.853.662.4+8.8
Other results6 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.
- ARC-AGI-1o3-pro by 22.33759.3+22.3
- vectara_factual_consistencyGemini 2.5 Pro by 16.39376.7+16.3
- Aider-Polygloto3-pro by 8.476.584.9+8.4
- AA Intelligenceo3-pro by 6.91521.9+6.9
- vectara_avg_summary_lengtho3-pro by 21 rating points106.4127.4+21 rating
- vectara_answer_ratetie99.1100tie
Questions people ask
Which is better, Gemini 2.5 Pro or o3-pro?
Gemini 2.5 Pro and o3-pro each win one of the three areas where both have results. Gemini 2.5 Pro wins facts; o3-pro wins following instructions. Gemini 2.5 Pro costs 89% less. They are level on reasoning.
Which is cheaper?
Gemini 2.5 Pro costs $1.25 per million input tokens and $10.00 per million output tokens; o3-pro costs $20.00 and $80.00. That makes Gemini 2.5 Pro about 89% cheaper for the same work.
How do you compare the two?
We use the 10 benchmark tests both models have published scores on. The verdict counts the 4 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 6 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.