Gemini 3.5 Flash vs GPT-5.6 Sol
Wins 1 of 8 areas
Following instructions
Wins 6 of 8 areas
Coding · Agents · Reasoning · Facts · Math · Long documents
GPT-5.6 Sol is the stronger all-rounder.Gemini 3.5 Flash is cheaper and better at following instructions.
Scores updated · 48 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 software07GPT-5.6 Sol7 of 7 tests
- AgentsCarrying out multi-step tasks on its own15GPT-5.6 Sol5 of 7 tests · 1 tie
- ReasoningHard problems that need careful thinking15GPT-5.6 Sol5 of 6 tests
- MathCompetition and research-level math04GPT-5.6 Sol4 of 4 tests
- FactsGetting facts right instead of making them up12GPT-5.6 Sol2 of 3 tests
- Long documentsFinding answers in very long texts01GPT-5.6 Sol1 of 1 test
- Following instructionsDoing exactly what it is asked20Gemini 3.5 Flash2 of 2 tests
- Images and chartsUnderstanding pictures, charts and video11Even1 each · 1 tie
Long documents rests on a single test.
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 3.5 Flash costs 56% less for the same work.
The biggest differences
The three tests each model wins by the widest margin. Scores are out of 100.
Where GPT-5.6 Sol pulls ahead
- Extremely hard research-level math problemsFrontierMath Tier 4+56.2points ahead
- Complex command-line tasks across many fieldsTerminal-Bench 4.0+33.3points ahead
- Unpublished advanced math problemsFrontierMath Tiers 1-3 (v2)+26.3points ahead
Where Gemini 3.5 Flash pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+30points ahead
- Common-sense trick questionsSimpleBench+11.9points ahead
- Long professional tasks in banking, consulting and lawAA ApexAgents+7.2points ahead
Every test, side by side
All 48 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGPT-5.6 Sol
- Terminal-Bench HardGPT-5.6 Sol by 2540.965.9+25
- LMArena · WebDevGPT-5.6 Sol by 121 rating points14991620+121 rating
- SWE-bench ProGPT-5.6 Sol by 9.555.164.6+9.5
- Terminal-Bench 2.1GPT-5.6 Sol by 9.378.788+9.3
- LiveBench · Agentic CodingGPT-5.6 Sol by 7.24956.2+7.2
- LiveBench · CodingGPT-5.6 Sol by 5.778.283.9+5.7
- SciCodeGPT-5.6 Sol by 3.253.957.1+3.2
AgentsGPT-5.6 Sol
- Terminal-Bench 4.0GPT-5.6 Sol by 33.36.639.9+33.3
- GDPValGPT-5.6 Sol by 20.435.255.6+20.4
- AA IT-Bench SREGPT-5.6 Sol by 15.940.356.2+15.9
- τ-Bench V3 · BankingGPT-5.6 Sol by 12.132.244.3+12.1
- AA ApexAgentsGemini 3.5 Flash by 7.247.139.9+7.2
- OSWorld-VerifiedGPT-5.6 Sol by 4.678.483+4.6
- MCP Atlastie83.683.6tie
ReasoningGPT-5.6 Sol
- ARC-AGI-2GPT-5.6 Sol by 20.472.192.5+20.4
- CritPtGPT-5.6 Sol by 19.213.132.3+19.2
- SimpleBenchGemini 3.5 Flash by 11.976.764.8+11.9
- LiveBench · ReasoningGPT-5.6 Sol by 9.78291.7+9.7
- Humanity's Last ExamGPT-5.6 Sol by 6.842.749.5+6.8
- GPQA DiamondGPT-5.6 Sol by 1.992.294.1+1.9
FactsGPT-5.6 Sol
- AA-Omniscience · Non-hallucinationGemini 3.5 Flash by 3037.87.8+30
- AA-Omniscience · AccuracyGPT-5.6 Sol by 851.459.4+8
- SimpleQA VerifiedGPT-5.6 Sol by 3.566.269.7+3.5
Images and chartsEven
- LMArena · VisionGemini 3.5 Flash by 31 rating points13101279+31 rating
- CharXiv (RQ)GPT-5.6 Sol by 1.684.285.8+1.6
- MMMU-Protie84.383.4tie
MathGPT-5.6 Sol
- FrontierMath Tier 4GPT-5.6 Sol by 56.226.883+56.2
- FrontierMath Tiers 1-3 (v2)GPT-5.6 Sol by 26.362.889.1+26.3
- LiveBench · MathematicsGPT-5.6 Sol by 888.296.2+8
- AIME 2026GPT-5.6 Sol by 4.99599.9+4.9
Following instructionsGemini 3.5 Flash
- LiveBench · Instruction FollowingGemini 3.5 Flash by 3.775.671.8+3.7
- IFBenchGemini 3.5 Flash by 3.676.372.7+3.6
Other results15 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-5.6 Sol by 362 rating points13491711+362 rating
- GDPval-AA v2 EloGPT-5.6 Sol by 361 rating points13491710+361 rating
- DeepSWE 1.1GPT-5.6 Sol by 363773+36
- DeepSWEGPT-5.6 Sol by 35.73772.7+35.7
- AA Agentic IndexGPT-5.6 Sol by 23.227.350.5+23.2
- livebench_data_analysisGPT-5.6 Sol by 14.964.979.8+14.9
- AA IntelligenceGPT-5.6 Sol by 14.432.647+14.4
- τ²-Bench Telecom (AA run)Gemini 3.5 Flash by 10.295.385.1+10.2
- Artificial Analysis Coding IndexGPT-5.6 Sol by 7.370.177.4+7.3
- LVBenchGPT-5.6 Sol by 5.876.382.1+5.8
- HiL-Bench (Tools-allowed)GPT-5.6 Sol by 4.627.732.3+4.6
- ARC-AGI-1GPT-5.6 Sol by 492.596.5+4
- livebench_languageGPT-5.6 Sol by 3.184.687.7+3.1
- ToolathlonGPT-5.6 Sol by 1.556.558+1.5
- AA-Omnisciencetie21.222tie
Questions people ask
Which is better, Gemini 3.5 Flash or GPT-5.6 Sol?
GPT-5.6 Sol wins six of the eight areas we test: coding, agents, reasoning, facts, math and long documents. Gemini 3.5 Flash wins following instructions, and costs 56% less. They are level on images and charts.
Which is better for coding?
GPT-5.6 Sol. It wins 7 of the 7 coding tests both models report; Gemini 3.5 Flash wins none.
Which is cheaper?
Gemini 3.5 Flash costs $1.50 per million input tokens and $9.00 per million output tokens; GPT-5.6 Sol costs $4.00 and $20.00. That makes Gemini 3.5 Flash about 56% cheaper for the same work.
How do you compare the two?
We use the 48 benchmark tests both models have published scores on. The verdict counts the 33 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 15 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.