GPT-5.5 vs GPT-6.1 Sol
Wins 2 of 8 areas
Coding · Long documents
Wins 6 of 8 areas
Agents · Reasoning · Facts · Images and charts · Math · Following instructions
GPT-6.1 Sol is the stronger all-rounder.GPT-5.5 is better at coding.
Both rank among the ten best models we track in reasoning and math.
Scores updated · 37 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.
- ReasoningHard problems that need careful thinking06GPT-6.1 Sol6 of 6 tests
- AgentsCarrying out multi-step tasks on its own03GPT-6.1 Sol3 of 3 tests
- FactsGetting facts right instead of making them up03GPT-6.1 Sol3 of 3 tests
- MathCompetition and research-level math02GPT-6.1 Sol2 of 3 tests · 1 tie
- Images and chartsUnderstanding pictures, charts and video01GPT-6.1 Sol1 of 2 tests · 1 tie
- Following instructionsDoing exactly what it is asked01GPT-6.1 Sol1 of 1 test
- CodingWriting and fixing software21GPT-5.52 of 4 tests · 1 tie
- Long documentsFinding answers in very long texts10GPT-5.51 of 1 test
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.
GPT-6.1 Sol costs 66% 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-6.1 Sol pulls ahead
- Solves new puzzle games it has never seenARC-AGI-3+52.3points ahead
- Complex command-line tasks across many fieldsTerminal-Bench 4.0+41.5points ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+34.7points ahead
Where GPT-5.5 pulls ahead
- Programming problems, refreshed regularlyLiveBench · Coding+1.8points ahead
- Code for real scientific research problemsSciCode+1.6points ahead
- Reasons across sets of long documentsAA-LCR+1.3points ahead
Every test, side by side
All 37 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGPT-5.5
- LMArena · WebDevGPT-6.1 Sol by 256 rating points14871743+256 rating
- LiveBench · CodingGPT-5.5 by 1.882.280.4+1.8
- SciCodeGPT-5.5 by 1.655.854.2+1.6
- LiveBench · Agentic Codingtie5454.5tie
AgentsGPT-6.1 Sol
- Terminal-Bench 4.0GPT-6.1 Sol by 41.514.656.1+41.5
- AA ApexAgentsGPT-6.1 Sol by 22.337.760+22.3
- GDPValGPT-6.1 Sol by 12.242.554.7+12.2
ReasoningGPT-6.1 Sol
- ARC-AGI-3GPT-6.1 Sol by 52.30.452.7+52.3
- SimpleBenchGPT-6.1 Sol by 13.96982.9+13.9
- ARC-AGI-2GPT-6.1 Sol by 9.28594.2+9.2
- Humanity's Last ExamGPT-6.1 Sol by 7.145.852.9+7.1
- CritPtGPT-6.1 Sol by 4.627.131.7+4.6
- LiveBench · ReasoningGPT-6.1 Sol by 2.989.792.6+2.9
FactsGPT-6.1 Sol
- AA-Omniscience · Non-hallucinationGPT-6.1 Sol by 34.71145.7+34.7
- SimpleQA VerifiedGPT-6.1 Sol by 10.96373.9+10.9
- AA-Omniscience · AccuracyGPT-6.1 Sol by 4.15862.1+4.1
Images and chartsGPT-6.1 Sol
- MMMU-ProGPT-6.1 Sol by 6.179.986+6.1
- LMArena · Visiontie12951286tie
MathGPT-6.1 Sol
- FrontierMath Tier 4GPT-6.1 Sol by 27.572.5100+27.5
- FrontierMath Tiers 1-3 (v2)GPT-6.1 Sol by 8.485.393.7+8.4
- LiveBench · Mathematicstie95.996.8tie
Following instructionsGPT-6.1 Sol
- LiveBench · Instruction FollowingGPT-6.1 Sol by 3.570.774.2+3.5
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.
- HiL-Bench (Tools-allowed)GPT-6.1 Sol by 22.639.762.3+22.6
- AA-OmniscienceGPT-6.1 Sol by 2120.541.5+21
- AA IntelligenceGPT-6.1 Sol by 13.438.451.8+13.4
- HealthBench ProfessionalGPT-6.1 Sol by 13.351.865.1+13.3
- HealthBench Professional length-adjustedGPT-6.1 Sol by 12.451.864.2+12.4
- DeepSWE 1.1GPT-6.1 Sol by 8.26775.2+8.2
- GDP (Surge AI)GPT-6.1 Sol by 6.124.931+6.1
- HealthBench Hard length-adjustedGPT-6.1 Sol by 4.731.536.2+4.7
- livebench_languageGPT-6.1 Sol by 2.787.490.1+2.7
- HealthBenchGPT-6.1 Sol by 256.558.5+2
- HealthBench length-adjustedGPT-6.1 Sol by 256.558.5+2
- ARC-AGI-1GPT-6.1 Sol by 1.59596.5+1.5
- livebench_data_analysisGPT-6.1 Sol by 1.181.682.7+1.1
- HealthBench Consensus length-adjustedtie95.696tie
Questions people ask
Which is better, GPT-5.5 or GPT-6.1 Sol?
GPT-6.1 Sol wins six of the eight areas we test: agents, reasoning, facts, images and charts, math and following instructions. GPT-5.5 wins coding and long documents.
Which is better for coding?
GPT-5.5. It wins 2 of the 4 coding tests both models report; GPT-6.1 Sol wins 1, and 1 is a tie.
Which is cheaper?
GPT-5.5 costs $5.00 per million input tokens and $30.00 per million output tokens; GPT-6.1 Sol costs $2.00 and $10.00. That makes GPT-6.1 Sol about 66% cheaper for the same work.
How do you compare the two?
We use the 37 benchmark tests both models have published scores on. The verdict counts the 23 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.