This is the commonly used size: we found no requirement published by the institution. Confirm it before your application.
Tips to get it right the first time
Place the card on a dark table so the edges are cropped cleanly.
When sharing a copy for KYC, consider the masked Aadhaar from myAadhaar, which hides the first digits.
Write the purpose and date on the copy before you hand it over.
How to do it with Requisito Listo
Open «Aadhaar card, both sides».
Scan the front and then the back: the app crops and straightens each side.
Both sides are placed on one A4 page at real size.
Share or save the PDF.
At the end you'll see a checklist: size, file weight, background and format. If something doesn't comply, it tells you what to fix before the portal rejects it.