Gemini 2.5 Pro vs Grok 4 Fast
Wins 3 of 7 areas
Coding · Facts · Images and charts
Wins 4 of 7 areas
Agents · Reasoning · Long documents · Following instructions
Grok 4 Fast wins more areas, narrowly.Gemini 2.5 Pro is better at coding.
Scores updated · 29 tests both models report · How we compare
Where each one wins
Tests won in each of the seven 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.
- ReasoningHard problems that need careful thinking02Grok 4 Fast2 of 4 tests · 2 ties
- AgentsCarrying out multi-step tasks on its own02Grok 4 Fast2 of 2 tests
- Long documentsFinding answers in very long texts01Grok 4 Fast1 of 1 test
- Following instructionsDoing exactly what it is asked01Grok 4 Fast1 of 1 test
- CodingWriting and fixing software30Gemini 2.5 Pro3 of 3 tests
- FactsGetting facts right instead of making them up21Gemini 2.5 Pro2 of 3 tests
- Images and chartsUnderstanding pictures, charts and video10Gemini 2.5 Pro1 of 1 test
Images and charts, 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.
Grok 4 Fast costs 94% less for the same work.
The biggest differences
The three tests each model wins by the widest margin. Scores are out of 100.
Where Grok 4 Fast pulls ahead
- Finds hard-to-locate facts by browsing the webBrowseComp+35points ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+22.6points ahead
- Reasons across sets of long documentsAA-LCR+4.7points ahead
Where Gemini 2.5 Pro pulls ahead
- Answers hard knowledge questions correctlyAA-Omniscience · Accuracy+16.3points ahead
- Harder college exam questions with imagesMMMU-Pro+13.1points ahead
- Hard command-line tasks in a real terminalTerminal-Bench Hard+7.6points ahead
Every test, side by side
All 29 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGemini 2.5 Pro
- Terminal-Bench HardGemini 2.5 Pro by 7.626.518.9+7.6
- LMArena · WebDevGemini 2.5 Pro by 65 rating points12241159+65 rating
- SciCodeGemini 2.5 Pro by 2.146.344.2+2.1
AgentsGrok 4 Fast
- BrowseCompGrok 4 Fast by 359.944.9+35
- GDPValGrok 4 Fast by 25.7025.7+25.7
ReasoningGrok 4 Fast
- GPQA DiamondGrok 4 Fast by 1.183.684.7+1.1
- Humanity's Last ExamGrok 4 Fast by 1.11819.1+1.1
- ARC-AGI-2tie4.95.3tie
- CritPttie2.62.9tie
FactsGemini 2.5 Pro
- AA-Omniscience · Non-hallucinationGrok 4 Fast by 22.69.131.7+22.6
- AA-Omniscience · AccuracyGemini 2.5 Pro by 16.33922.8+16.3
- Vectara HHEM hallucination ratelower is betterGemini 2.5 Pro by 13.2720.2+13.2
Images and chartsGemini 2.5 Pro
- MMMU-ProGemini 2.5 Pro by 13.174.961.8+13.1
Following instructionsGrok 4 Fast
- IFBenchGrok 4 Fast by 1.848.750.5+1.8
Other results14 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.
- SimpleQAGrok 4 Fast by 44.250.895+44.2
- AA Agentic IndexGrok 4 Fast by 363.539.5+36
- HMMT 2025Grok 4 Fast by 27.665.793.3+27.6
- Artificial Analysis Coding IndexGemini 2.5 Pro by 19.346.727.4+19.3
- AA-OmniscienceGemini 2.5 Pro by 13.6-16.4-29.9+13.6
- vectara_factual_consistencyGemini 2.5 Pro by 13.29379.8+13.2
- BrowseComp-ZHGrok 4 Fast by 12.832.245+12.8
- τ²-Bench Telecom (AA run)Grok 4 Fast by 11.754.165.8+11.7
- ARC-AGI-1Grok 4 Fast by 11.53748.5+11.5
- AIME 2025Grok 4 Fast by 98392+9
- vectara_avg_summary_lengthGrok 4 Fast by 67.5 rating points106.4173.9+67.5 rating
- LiveCodeBenchGrok 4 Fast by 5.874.280+5.8
- AA IntelligenceGrok 4 Fast by 2.91517.9+2.9
- vectara_answer_ratetie99.199.5tie
Questions people ask
Which is better, Gemini 2.5 Pro or Grok 4 Fast?
Grok 4 Fast wins four of the seven areas where both have results: agents, reasoning, long documents and following instructions. Gemini 2.5 Pro wins coding, facts and images and charts.
Which is better for coding?
Gemini 2.5 Pro. It wins 3 of the 3 coding tests both models report; Grok 4 Fast wins none.
Which is cheaper?
Gemini 2.5 Pro costs $1.25 per million input tokens and $10.00 per million output tokens; Grok 4 Fast costs $0.20 and $0.50. That makes Grok 4 Fast about 94% cheaper for the same work.
How do you compare the two?
We use the 29 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 14 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.