Gemini 2.5 Pro vs Mercury 2
Wins 4 of 6 areas
Coding · Reasoning · Facts · Long documents
Wins 1 of 6 areas
Following instructions
Gemini 2.5 Pro is the stronger all-rounder.Mercury 2 is cheaper and better at following instructions.
Scores updated · 25 tests both models report · How we compare
Where each one wins
Tests won in each of the six 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.
- CodingWriting and fixing software30Gemini 2.5 Pro3 of 4 tests · 1 tie
- ReasoningHard problems that need careful thinking20Gemini 2.5 Pro2 of 3 tests · 1 tie
- FactsGetting facts right instead of making them up20Gemini 2.5 Pro2 of 3 tests · 1 tie
- Long documentsFinding answers in very long texts10Gemini 2.5 Pro1 of 1 test
- Following instructionsDoing exactly what it is asked01Mercury 21 of 1 test
- AgentsCarrying out multi-step tasks on its own00Even0 each · 3 ties
Long documents 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.
Mercury 2 costs 91% 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
- Reasons across sets of long documentsAA-LCR+25.3points ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+17.9points ahead
- Code for real scientific research problemsSciCode+8.6points ahead
Where Mercury 2 pulls ahead
- Follows unfamiliar, precisely checkable instructionsIFBench+21.1points ahead
Every test, side by side
All 25 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGemini 2.5 Pro
- SciCodeGemini 2.5 Pro by 8.646.337.7+8.6
- LMArena · WebDevGemini 2.5 Pro by 58 rating points12241166+58 rating
- Terminal-Bench 2.1Gemini 2.5 Pro by 1.228.527.3+1.2
- Terminal-Bench Hardtie26.526.5tie
AgentsEven
- τ-Bench V3 · Bankingtie9.79.5tie
- GDPValtie00tie
- Terminal-Bench 4.0tie00tie
ReasoningGemini 2.5 Pro
- GPQA DiamondGemini 2.5 Pro by 6.683.677+6.6
- CritPtGemini 2.5 Pro by 1.82.60.8+1.8
- Humanity's Last Examtie1817.1tie
FactsGemini 2.5 Pro
- AA-Omniscience · AccuracyGemini 2.5 Pro by 17.93921.2+17.9
- Vectara HHEM hallucination ratelower is betterGemini 2.5 Pro by 5.3712.3+5.3
- AA-Omniscience · Non-hallucinationtie9.18.8tie
Following instructionsMercury 2
- IFBenchMercury 2 by 21.148.769.8+21.1
Other results10 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.
- AA-OmniscienceGemini 2.5 Pro by 34.4-16.4-50.7+34.4
- τ²-Bench Telecom (AA run)Mercury 2 by 16.754.170.8+16.7
- Artificial Analysis Coding IndexGemini 2.5 Pro by 15.646.731.1+15.6
- AIME 2025Mercury 2 by 8.18391.1+8.1
- LiveCodeBenchGemini 2.5 Pro by 7.274.267+7.2
- vectara_factual_consistencyGemini 2.5 Pro by 5.39387.7+5.3
- vectara_avg_summary_lengthMercury 2 by 42.7 rating points106.4149.1+42.7 rating
- AA IntelligenceGemini 2.5 Pro by 1.21513.8+1.2
- vectara_answer_ratetie99.1100tie
- AA Agentic Indextie3.54tie
Questions people ask
Which is better, Gemini 2.5 Pro or Mercury 2?
Gemini 2.5 Pro wins four of the six areas where both have results: coding, reasoning, facts and long documents. Mercury 2 wins following instructions, and costs 91% less. They are level on agents.
Which is better for coding?
Gemini 2.5 Pro. It wins 3 of the 4 coding tests both models report; Mercury 2 wins none, and 1 is a tie.
Which is cheaper?
Gemini 2.5 Pro costs $1.25 per million input tokens and $10.00 per million output tokens; Mercury 2 costs $0.25 and $0.75. That makes Mercury 2 about 91% cheaper for the same work.
How do you compare the two?
We use the 25 benchmark tests both models have published scores on. The verdict counts the 15 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 10 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.