19 Aug 2018 · 1 min read

Protecting Your Privacy in a Post-Aadhar India

With more and more online and offline services demanding Indian citizens to provide their Aadhar number for availing their services without any legal basis and necessity under the pretense of proving your identity, it does raise more than a few privacy concerns. The unique Aadhar number that is assigned to a person and is printed on the Aadhar Card is a 12 digit number where the first 11 digits are random and the last number is a checksum based on <a rel="noopener nofollow noreferrer external" target="_blank" href="https://en.wikipedia.org/wiki/Verhoeff_algorithm">Verhoeff</a>’s algorithm (<a rel="noopener nofollow noreferrer external" target="_blank" href="https://www.quora.com/What-is-the-structure-of-ones-Aadhar-Card-UID-number">source</a>) that can be used to verify the validity of the complete number. So to get a valid Aadhar number all you need is 11 random digits and their <a rel="noopener nofollow noreferrer external" target="_blank" href="https://en.wikipedia.org/wiki/Verhoeff_algorithm">Verhoeff</a> checksum as the 12th digit. One example number that passes the above scheme and hence is valid is <code>999999990019</code>. This is a test number recommend by UIDAI but many more numbers can be generated using the same scheme. So if a system just checks the validity of a Aadhar number using the above scheme you can safely enter <code>999999990019</code> and continue using their services while protecting you privacy. That’s what I did for using Amazon Pay :) <h3 id="virtual-number"><a class="zola-anchor" href="#virtual-number" aria-label="Anchor link for: virtual-number">🔗</a> Virtual Number</h3> If you still feel like you have to use a legitimate number but want to minimise infringement of your right to privacy, consider giving out a “Virtual Number” that is temporary number that points to your actual Aadhar number without actually revealing your real Aadhar number. You can use the Virtual Number/ID (VID) generator at the offical UIDAI <a rel="noopener nofollow noreferrer external" target="_blank" href="https://resident.uidai.gov.in/web/resident/vidgeneration">website</a> or the android <a rel="noopener nofollow noreferrer external" target="_blank" href="https://play.google.com/store/apps/details?id=in.gov.uidai.mAadhaarPlus">mobile app</a>. Also next time someone asks for a photocopy of your Aadhar card, tell them to f*ck off.