Gemini 3.1 Flash Lite Preview vs GPT-5.5
Wins 2 of 8 areas
Facts · Following instructions
Wins 6 of 8 areas
Coding · Agents · Reasoning · Images and charts · Math · Long documents
GPT-5.5 is the stronger all-rounder.Gemini 3.1 Flash Lite Preview is cheaper and better at facts.
Scores updated · 30 tests both models report · How we compare
Where each one wins
Tests won in each of the eight areas we test. 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 software04GPT-5.54 of 4 tests
- AgentsCarrying out multi-step tasks on its own04GPT-5.54 of 4 tests
- ReasoningHard problems that need careful thinking03GPT-5.53 of 3 tests
- Images and chartsUnderstanding pictures, charts and video02GPT-5.52 of 2 tests
- MathCompetition and research-level math01GPT-5.51 of 1 test
- Long documentsFinding answers in very long texts01GPT-5.51 of 1 test
- FactsGetting facts right instead of making them up21Gemini 3.1 Flash Lite Preview2 of 3 tests
- Following instructionsDoing exactly what it is asked10Gemini 3.1 Flash Lite Preview1 of 1 test
Math, 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.
Gemini 3.1 Flash Lite Preview costs 95% 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 pulls ahead
- Unpublished advanced math problemsFrontierMath Tiers 1-3 (v2)+57.6points ahead
- Command-line tasks in a real terminalTerminal-Bench 2.1+53.2points ahead
- Hard command-line tasks in a real terminalTerminal-Bench Hard+36.4points ahead
Where Gemini 3.1 Flash Lite Preview pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+6.3points ahead
- Follows unfamiliar, precisely checkable instructionsIFBench+1.3points ahead
Every test, side by side
All 30 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGPT-5.5
- Terminal-Bench 2.1GPT-5.5 by 53.231.184.3+53.2
- Terminal-Bench HardGPT-5.5 by 36.424.260.6+36.4
- LMArena · WebDevGPT-5.5 by 259 rating points12541513+259 rating
- SciCodeGPT-5.5 by 12.443.455.8+12.4
AgentsGPT-5.5
- GDPValGPT-5.5 by 42.7042.7+42.7
- τ-Bench V3 · BankingGPT-5.5 by 29.39.739+29.3
- AA ApexAgentsGPT-5.5 by 25.512.237.7+25.5
- Terminal-Bench 4.0GPT-5.5 by 14.10.514.6+14.1
ReasoningGPT-5.5
- Humanity's Last ExamGPT-5.5 by 28.617.245.8+28.6
- CritPtGPT-5.5 by 261.127.1+26
- GPQA DiamondGPT-5.5 by 11.382.293.5+11.3
FactsGemini 3.1 Flash Lite Preview
- AA-Omniscience · AccuracyGPT-5.5 by 21.736.358+21.7
- AA-Omniscience · Non-hallucinationGemini 3.1 Flash Lite Preview by 6.317.311+6.3
- Vectara HHEM hallucination ratelower is betterGemini 3.1 Flash Lite Preview by 1.18.29.3+1.1
Images and chartsGPT-5.5
- LMArena · VisionGPT-5.5 by 52 rating points12401292+52 rating
- MMMU-ProGPT-5.5 by 4.475.579.9+4.4
Following instructionsGemini 3.1 Flash Lite Preview
- IFBenchGemini 3.1 Flash Lite Preview by 1.377.275.9+1.3
Other results11 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.
- GDPval-AA v2GPT-5.5 by 867 rating points6421509+867 rating
- τ²-Bench Telecom (AA run)GPT-5.5 by 62.631.393.9+62.6
- Artificial Analysis Coding IndexGPT-5.5 by 40.234.774.9+40.2
- AA-OmniscienceGPT-5.5 by 36.9-16.420.5+36.9
- AA Agentic IndexGPT-5.5 by 34.13.237.3+34.1
- AA IntelligenceGPT-5.5 by 22.815.638.4+22.8
- Finance Agent v2GPT-5.5 by 21.83051.8+21.8
- vectara_avg_summary_lengthGPT-5.5 by 67 rating points62.6129.6+67 rating
- Legal Agent BenchmarkGPT-5.5 by 2.102.1+2.1
- vectara_factual_consistencyGemini 3.1 Flash Lite Preview by 1.191.890.7+1.1
- vectara_answer_ratetie99.6100tie
Questions people ask
Which is better, Gemini 3.1 Flash Lite Preview or GPT-5.5?
GPT-5.5 wins six of the eight areas we test: coding, agents, reasoning, images and charts, math and long documents. Gemini 3.1 Flash Lite Preview wins facts and following instructions, and costs 95% less.
Which is better for coding?
GPT-5.5. It wins 4 of the 4 coding tests both models report; Gemini 3.1 Flash Lite Preview wins none.
Which is cheaper?
Gemini 3.1 Flash Lite Preview costs $0.25 per million input tokens and $1.50 per million output tokens; GPT-5.5 costs $5.00 and $30.00. That makes Gemini 3.1 Flash Lite Preview about 95% cheaper for the same work.
How do you compare the two?
We use the 30 benchmark tests both models have published scores on. The verdict counts the 19 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 11 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.