Briefing
SKY-001 vs GPT-6 Astra — speed, cost and accuracy comparison
Updated 2026-10-21. Independent summary, not a Skyfall AI publication.
The comparison people repeat is SKY-001 versus GPT-6 Astra on Skyfall’s own construction tasks. Skyfall publishes it as a 3D CAD benchmark and a BIM benchmark. This site copies those vendor-reported figures and labels them as such.
The gap Skyfall emphasizes is not a huge accuracy blowout. On CAD intersection-over-union the two are close. The gap they emphasize is time and cost: seconds and a fraction of a cent, versus minutes and a much larger reported spend per case.
How to read the table
IoU (intersection over union) is a overlap score against a reference shape. Higher is better. Time and cost are lower-is-better. None of these numbers were measured in a lab run by sky-001.org.
Skyfall’s product page headlines list CAD at 3.9 seconds and $0.005 versus 199 seconds and $0.75, and BIM at 1.22 seconds and $0.0024 versus 144.6 seconds and $0.446. IoU figures quoted from the 19 October 2026 introduction are CAD 79.7% versus 79.1%, and BIM 43.6% versus 40.6%. The live page has also shown nearby IoU bars, so treat the second digit as the company’s reported range.
What the comparison does not prove
A vendor benchmark is not a purchase order and not a safety certificate. Close IoU on a company’s own set can move with the prompt, the scorer, or the reference. Speed and cost, if they hold up under outside review, are the more striking part of the SKY-001 vs GPT-6 Astra story.
Grok and other models appear on Skyfall’s chart as well. This article stays on the Astra pair because that is the headline comparison. See the table on our homepage for the same six rows.
| Metric | SKY-001 | GPT-6 Astra |
|---|---|---|
| 3D CAD IoU (higher is better) | 79.7% | 79.1% |
| 3D CAD time per case | 3.9 s | 199 s |
| 3D CAD cost per case | $0.005 | $0.75 |
| BIM IoU (higher is better) | 43.6% | 40.6% |
| BIM time per plan | 1.22 s | 144.6 s |
| BIM cost per plan | $0.0024 | $0.446 |
Source: Skyfall AI, skyfall.ai/sky-001, checked 21 October 2026, alongside the 19 October 2026 introduction. Time and cost headlines compare SKY-001 with GPT-6 Astra (CAD 3.9 s vs 199 s, $0.005 vs $0.75; BIM 1.22 s vs 144.6 s, $0.0024 vs $0.446). On the same page the CAD IoU chart lists SKY-001 at 79.7% and GPT-6 Astra at 79.1%, which is also the “best LLM” CAD figure in the headline. The BIM IoU chart lists SKY-001 at 43.6%, Gemini 3.8 Flash at 42.3%, and GPT-6 Astra at 40.6%. The 42.3% headline is Gemini on that chart, not Astra. These are vendor-reported results. sky-001.org did not run the tests.
Figures on this page are vendor-reported and were not re-run here.
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