Claude Opus 4.5 vs GPT-6 Astra
Wins 0 of 8 areas
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Wins 8 of 8 areas
Coding · Agents · Reasoning · Facts · Images and charts · Math · Long documents · Following instructions
GPT-6 Astra is the stronger all-rounder.Claude Opus 4.5 is cheaper.
Scores updated · 32 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 thinking05GPT-6 Astra5 of 5 tests
- FactsGetting facts right instead of making them up04GPT-6 Astra4 of 4 tests
- CodingWriting and fixing software03GPT-6 Astra3 of 4 tests · 1 tie
- MathCompetition and research-level math03GPT-6 Astra3 of 3 tests
- AgentsCarrying out multi-step tasks on its own02GPT-6 Astra2 of 2 tests
- Images and chartsUnderstanding pictures, charts and video01GPT-6 Astra1 of 1 test
- Long documentsFinding answers in very long texts01GPT-6 Astra1 of 1 test
- Following instructionsDoing exactly what it is asked01GPT-6 Astra1 of 1 test
Images and charts, 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.
Claude Opus 4.5 costs 50% 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-6 Astra pulls ahead
- Extremely hard research-level math problemsFrontierMath Tier 4+92.7points ahead
- Unpublished advanced math problemsFrontierMath Tiers 1-3 (v2)+59.3points ahead
- Abstract visual puzzles that people can solveARC-AGI-2+57.4points ahead
Where Claude Opus 4.5 pulls ahead
No clear win on a test scored out of 100.
Every test, side by side
All 32 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 304 rating points14691773+304 rating
- LiveBench · Agentic CodingGPT-6 Astra by 17.639.757.3+17.6
- SciCodeGPT-6 Astra by 749.556.5+7
- LiveBench · Codingtie79.780.4tie
AgentsGPT-6 Astra
- BrowseCompGPT-6 Astra by 54.53791.5+54.5
- GDPValGPT-6 Astra by 6.347.353.6+6.3
ReasoningGPT-6 Astra
- ARC-AGI-2GPT-6 Astra by 57.437.695+57.4
- CritPtGPT-6 Astra by 27.14.631.7+27.1
- Humanity's Last ExamGPT-6 Astra by 24.630.154.7+24.6
- LiveBench · ReasoningGPT-6 Astra by 12.680.192.7+12.6
- GPQA DiamondGPT-6 Astra by 9.586.696.1+9.5
FactsGPT-6 Astra
- SimpleQA VerifiedGPT-6 Astra by 29.945.775.6+29.9
- AA-Omniscience · AccuracyGPT-6 Astra by 1646.662.6+16
- AA-Omniscience · Non-hallucinationGPT-6 Astra by 9.73948.7+9.7
- Vectara HHEM hallucination ratelower is betterGPT-6 Astra by 2.210.98.7+2.2
MathGPT-6 Astra
- FrontierMath Tier 4GPT-6 Astra by 92.74.997.6+92.7
- FrontierMath Tiers 1-3 (v2)GPT-6 Astra by 59.334.493.7+59.3
- LiveBench · MathematicsGPT-6 Astra by 6.490.496.8+6.4
Following instructionsGPT-6 Astra
- LiveBench · Instruction FollowingGPT-6 Astra by 1362.575.6+13
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.
- AA-OmniscienceGPT-6 Astra by 29.41443.4+29.4
- Artificial Analysis Coding IndexGPT-6 Astra by 29.147.876.9+29.1
- AA IntelligenceGPT-6 Astra by 23.629.152.7+23.6
- ARC-AGI-1GPT-6 Astra by 15.58297.5+15.5
- HLE (with tools)GPT-6 Astra by 13.843.457.2+13.8
- livebench_data_analysisGPT-6 Astra by 8.674.483+8.6
- AA Agentic IndexClaude Opus 4.5 by 8.159.651.5+8.1
- livebench_languageGPT-6 Astra by 8.181.389.4+8.1
- vectara_avg_summary_lengthGPT-6 Astra by 34 rating points114.5148.5+34 rating
- vectara_factual_consistencyGPT-6 Astra by 2.289.191.3+2.2
- vectara_answer_rateGPT-6 Astra by 1.398.7100+1.3
Questions people ask
Which is better, Claude Opus 4.5 or GPT-6 Astra?
GPT-6 Astra wins all eight areas we test: coding, agents, reasoning, facts, images and charts, math, long documents and following instructions. Claude Opus 4.5 wins none, but costs 50% less.
Which is better for coding?
GPT-6 Astra. It wins 3 of the 4 coding tests both models report; Claude Opus 4.5 wins none, and 1 is a tie.
Which is cheaper?
Claude Opus 4.5 costs $5.00 per million input tokens and $25.00 per million output tokens; GPT-6 Astra costs $10.00 and $50.00. That makes Claude Opus 4.5 about 50% cheaper for the same work.
How do you compare the two?
We use the 32 benchmark tests both models have published scores on. The verdict counts the 21 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.