Gemini 3.8 Flash vs GPT-5.6 Sol
Wins 2 of 8 areas
Images and charts · Following instructions
Wins 5 of 8 areas
Coding · Agents · Reasoning · Math · Long documents
GPT-5.6 Sol is the stronger all-rounder.Gemini 3.8 Flash is cheaper and better at images and charts.
Both rank among the ten best models we track in reasoning.
Scores updated · 45 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 software03GPT-5.6 Sol3 of 5 tests · 2 ties
- AgentsCarrying out multi-step tasks on its own03GPT-5.6 Sol3 of 4 tests · 1 tie
- MathCompetition and research-level math03GPT-5.6 Sol3 of 3 tests
- ReasoningHard problems that need careful thinking34GPT-5.6 Sol4 of 7 tests
- Long documentsFinding answers in very long texts01GPT-5.6 Sol1 of 1 test
- Images and chartsUnderstanding pictures, charts and video20Gemini 3.8 Flash2 of 3 tests · 1 tie
- Following instructionsDoing exactly what it is asked10Gemini 3.8 Flash1 of 1 test
- FactsGetting facts right instead of making them up11Even1 each · 1 tie
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 3.8 Flash costs 81% 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+61points ahead
- Unpublished advanced math problemsFrontierMath Tiers 1-3 (v2)+20.7points ahead
- Complex command-line tasks across many fieldsTerminal-Bench 4.0+20.2points ahead
Where Gemini 3.8 Flash pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+37points ahead
- Common-sense trick questionsSimpleBench+17.6points ahead
- Follows detailed instructions exactlyLiveBench · Instruction Following+9.5points ahead
Every test, side by side
All 45 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGPT-5.6 Sol
- LiveBench · CodingGPT-5.6 Sol by 11.472.583.9+11.4
- LMArena · WebDevGPT-5.6 Sol by 30 rating points15861616+30 rating
- LiveBench · Agentic CodingGPT-5.6 Sol by 254.256.2+2
- SciCodetie56.657.1tie
- Terminal-Bench 2.1tie87.688tie
AgentsGPT-5.6 Sol
- Terminal-Bench 4.0GPT-5.6 Sol by 20.219.739.9+20.2
- GDPValGPT-5.6 Sol by 8.646.855.4+8.6
- AA IT-Bench SREGPT-5.6 Sol by 3.752.556.2+3.7
- τ-Bench V3 · Bankingtie44.944.3tie
ReasoningGPT-5.6 Sol
- SimpleBenchGemini 3.8 Flash by 17.682.464.8+17.6
- CritPtGPT-5.6 Sol by 1418.332.3+14
- ARC-AGI-2GPT-5.6 Sol by 3.389.292.5+3.3
- ARC-AGI-3Gemini 3.8 Flash by 2.610.47.8+2.6
- LiveBench · ReasoningGPT-5.6 Sol by 2.489.391.7+2.4
- Humanity's Last ExamGPT-5.6 Sol by 1.747.849.5+1.7
- GPQA DiamondGemini 3.8 Flash by 1.295.394.1+1.2
FactsEven
- AA-Omniscience · Non-hallucinationGemini 3.8 Flash by 3744.87.8+37
- AA-Omniscience · AccuracyGPT-5.6 Sol by 4.854.659.4+4.8
- SimpleQA Verifiedtie69.769.7tie
Images and chartsGemini 3.8 Flash
- LMArena · VisionGemini 3.8 Flash by 33 rating points13141281+33 rating
- MMMU-ProGemini 3.8 Flash by 2.285.683.4+2.2
- CharXiv (RQ)tie86.285.8tie
MathGPT-5.6 Sol
- FrontierMath Tier 4GPT-5.6 Sol by 6121.983+61
- FrontierMath Tiers 1-3 (v2)GPT-5.6 Sol by 20.768.489.1+20.7
- LiveBench · MathematicsGPT-5.6 Sol by 4.691.696.2+4.6
Following instructionsGemini 3.8 Flash
- LiveBench · Instruction FollowingGemini 3.8 Flash by 9.581.471.8+9.5
Other results18 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.
- livebench_data_analysisGPT-5.6 Sol by 25.85479.8+25.8
- Terminal-Bench 4.0GPT-5.6 Sol by 18.219.137.3+18.2
- GDPval-AA v2GPT-5.6 Sol by 166 rating points15451711+166 rating
- GDPval-AA v2 EloGPT-5.6 Sol by 165 rating points15451710+165 rating
- AA Agentic IndexGPT-5.6 Sol by 9.441.150.5+9.4
- HiL-Bench (Tools-allowed)Gemini 3.8 Flash by 9.241.532.3+9.2
- AA-OmniscienceGemini 3.8 Flash by 7.629.622+7.6
- AA IntelligenceGPT-5.6 Sol by 6.140.947+6.1
- GDP.PDF (All pass rate)GPT-5.6 Sol by 53540+5
- LVBenchGemini 3.8 Flash by 587.182.1+5
- GDP (Surge AI)Gemini 3.8 Flash by 4.33530.7+4.3
- OSWorld 2.0GPT-5.6 Sol by 3.65962.6+3.6
- OSWorld 2.0 (partial)GPT-5.6 Sol by 3.65962.6+3.6
- ARC-AGI-1Gemini 3.8 Flash by 298.596.5+2
- Artificial Analysis Coding IndexGPT-5.6 Sol by 1.176.377.4+1.1
- DeepSWE 1.1tie73.773tie
- HLE-Verifiedtie54.954.5tie
- livebench_languagetie87.887.7tie
Questions people ask
Which is better, Gemini 3.8 Flash or GPT-5.6 Sol?
GPT-5.6 Sol wins five of the eight areas we test: coding, agents, reasoning, math and long documents. Gemini 3.8 Flash wins images and charts and following instructions, and costs 81% less. They are level on facts.
Which is better for coding?
GPT-5.6 Sol. It wins 3 of the 5 coding tests both models report; Gemini 3.8 Flash wins none, and 2 are ties.
Which is cheaper?
Gemini 3.8 Flash costs $0.75 per million input tokens and $3.75 per million output tokens; GPT-5.6 Sol costs $4.00 and $20.00. That makes Gemini 3.8 Flash about 81% cheaper for the same work.
How do you compare the two?
We use the 45 benchmark tests both models have published scores on. The verdict counts the 27 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 18 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.