GPT-5.6 Sol vs GPT-6 Astra
Wins 2 of 8 areas
Agents · Long documents
Wins 6 of 8 areas
Coding · Reasoning · Facts · Images and charts · Math · Following instructions
GPT-6 Astra is the stronger all-rounder.GPT-5.6 Sol is cheaper and better at agents.
Both rank among the ten best models we track in reasoning and math.
Scores updated · 53 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 Astra6 of 7 tests · 1 tie
- FactsGetting facts right instead of making them up04GPT-6 Astra4 of 4 tests
- MathCompetition and research-level math02GPT-6 Astra2 of 3 tests · 1 tie
- CodingWriting and fixing software12GPT-6 Astra2 of 5 tests · 2 ties
- Images and chartsUnderstanding pictures, charts and video01GPT-6 Astra1 of 2 tests · 1 tie
- Following instructionsDoing exactly what it is asked01GPT-6 Astra1 of 1 test
- AgentsCarrying out multi-step tasks on its own32GPT-5.6 Sol3 of 5 tests
- Long documentsFinding answers in very long texts10GPT-5.6 Sol1 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-5.6 Sol costs 60% 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 Astra pulls ahead
- Solves new puzzle games it has never seenARC-AGI-3+92.1points ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+40.9points ahead
- Complex command-line tasks across many fieldsTerminal-Bench 4.0+19.2points ahead
Where GPT-5.6 Sol pulls ahead
- Finds the root cause of IT system incidentsAA IT-Bench SRE+7.6points ahead
- Programming problems, refreshed regularlyLiveBench · Coding+3.5points ahead
- Reasons across sets of long documentsAA-LCR+3.3points ahead
Every test, side by side
All 53 tests both models report. The winning score is in its model's colour; marks a score checked independently.
CodingGPT-6 Astra
- LMArena · WebDevGPT-6 Astra by 158 rating points16161774+158 rating
- LiveBench · CodingGPT-5.6 Sol by 3.583.980.4+3.5
- LiveBench · Agentic CodingGPT-6 Astra by 1.156.257.3+1.1
- SciCodetie57.156.5tie
- Terminal-Bench 2.1tie8888.4tie
AgentsGPT-5.6 Sol
- Terminal-Bench 4.0GPT-6 Astra by 19.239.959.1+19.2
- AA IT-Bench SREGPT-5.6 Sol by 7.656.248.6+7.6
- τ-Bench V3 · BankingGPT-5.6 Sol by 2.944.341.4+2.9
- GDPValGPT-5.6 Sol by 1.855.453.6+1.8
- BrowseCompGPT-6 Astra by 1.190.491.5+1.1
ReasoningGPT-6 Astra
- ARC-AGI-3GPT-6 Astra by 92.17.899.9+92.1
- SimpleBenchGPT-6 Astra by 18.864.883.6+18.8
- Humanity's Last ExamGPT-6 Astra by 5.249.554.7+5.2
- ARC-AGI-2GPT-6 Astra by 2.592.595+2.5
- GPQA DiamondGPT-6 Astra by 294.196.1+2
- LiveBench · ReasoningGPT-6 Astra by 191.792.7+1
- CritPttie32.331.7tie
FactsGPT-6 Astra
- AA-Omniscience · Non-hallucinationGPT-6 Astra by 40.97.848.7+40.9
- SimpleQA VerifiedGPT-6 Astra by 5.969.775.6+5.9
- Vectara HHEM hallucination ratelower is betterGPT-6 Astra by 3.712.48.7+3.7
- AA-Omniscience · AccuracyGPT-6 Astra by 3.259.462.6+3.2
Images and chartsGPT-6 Astra
- MMMU-ProGPT-6 Astra by 3.583.486.9+3.5
- LMArena · Visiontie12811280tie
MathGPT-6 Astra
- FrontierMath Tier 4GPT-6 Astra by 14.68397.6+14.6
- FrontierMath Tiers 1-3 (v2)GPT-6 Astra by 4.689.193.7+4.6
- LiveBench · Mathematicstie96.296.8tie
Following instructionsGPT-6 Astra
- LiveBench · Instruction FollowingGPT-6 Astra by 3.771.875.6+3.7
Other results25 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.
- Terminal-Bench-Science 0.1GPT-6 Astra by 42.222.464.6+42.2
- HiL-Bench (Tools-allowed)GPT-6 Astra by 3332.365.3+33
- AA-OmniscienceGPT-6 Astra by 21.42243.4+21.4
- Terminal-Bench 4.0GPT-6 Astra by 20.637.357.9+20.6
- OSWorld 2.0GPT-6 Astra by 1062.672.6+10
- PostTrainBenchGPT-6 Astra by 8.136.244.3+8.1
- Agents' Last ExamGPT-6 Astra by 6.652.759.3+6.6
- AA IntelligenceGPT-6 Astra by 5.74752.7+5.7
- LVBenchGPT-6 Astra by 5.482.187.5+5.4
- GDPval-AA 2.1GPT-5.6 Sol by 46 rating points15881542+46 rating
- HealthBench Professional length-adjustedGPT-6 Astra by 4.260.564.7+4.2
- vectara_factual_consistencyGPT-6 Astra by 3.787.691.3+3.7
- HealthBench Hard length-adjustedGPT-6 Astra by 3.533.136.6+3.5
- livebench_data_analysisGPT-6 Astra by 3.279.883+3.2
- HealthBench ProfessionalGPT-6 Astra by 2.960.563.4+2.9
- vectara_avg_summary_lengthGPT-6 Astra by 17.4 rating points131.1148.5+17.4 rating
- livebench_languageGPT-6 Astra by 1.787.789.4+1.7
- HealthBench length-adjustedGPT-6 Astra by 1.35758.3+1.3
- DeepSWE 1.1GPT-6 Astra by 1.17374.1+1.1
- AA Agentic IndexGPT-6 Astra by 150.551.5+1
- ARC-AGI-1GPT-6 Astra by 196.597.5+1
- vectara_answer_ratetie99.1100tie
- Artificial Analysis Coding Indextie77.476.9tie
- Multimodal Troubleshooting Virologytie55.555.8tie
- HealthBench Consensus length-adjustedtie95.595.5tie
Questions people ask
Which is better, GPT-5.6 Sol or GPT-6 Astra?
GPT-6 Astra wins six of the eight areas we test: coding, reasoning, facts, images and charts, math and following instructions. GPT-5.6 Sol wins agents and long documents, and costs 60% less.
Which is better for coding?
GPT-6 Astra. It wins 2 of the 5 coding tests both models report; GPT-5.6 Sol wins 1, and 2 are ties.
Which is cheaper?
GPT-5.6 Sol costs $4.00 per million input tokens and $20.00 per million output tokens; GPT-6 Astra costs $10.00 and $50.00. That makes GPT-5.6 Sol about 60% cheaper for the same work.
How do you compare the two?
We use the 53 benchmark tests both models have published scores on. The verdict counts the 28 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 25 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.