The bedrock of India Stack is a set of digital identity products centered around Aadhaar, India’s national identity program. More than 1.31 bn (95%) Indians possess an Aadhaar number, which allows them to perform a number of actions including:

  • Remotely authenticating any one, or indeed all, of these attributes via two-factor or biometric authentication: name, age, address, mobile number, email address, gender.
  • Receiving digitally signed and universally accepted copies of lifetime records such as driver’s licenses, educational diplomas, insurance policies, and more.
  • Signing documents or messages using a government-backed digital signature service.

Aadhaar Aadhaar Authentication

The entire point of the Aadhaar program is to seed the population with secure, versatile digital IDs that can be used to quickly authenticate a user’s identity. There are currently a variety of ways in which a petitioner can prove a user’s identity using Aadhaar:

The utilities offered by Aadhaar can be used to build all kinds of identity workflows. For example, a developer could build a social media platform that only allows women users to sign up. In another case, an app could use e-auth to verify that a user's claimed address, while leaving all other fields anonymous.

The possibilities are manifold, and developers are encouraged to come up with novel ways to use this public digital infrastructure. Having said that, readers should be aware that e-auth and e-KYC services are only available to banks, licensed NBFCs, telecom companies, and government bodies.

Developers belonging to other organizations must use QR code scans, e-Aadhaar, or offline XML in order to prove a customer’s identity using Aadhaar.

Here are some relevant resources about Aadhaar authentication services:

The API specification for e-KYC The UIDAI Developer Section

Statistics detailing the number of e-auth requests in real time

1.3 billion

Aadhaar Generated

0.5 billion

Aadhaar Updated

63.6 billion

Authentication Done

10.4 billion

eKYC Done

Digilocker Digilocker

DigiLocker is a public utility provided to Aadhaar holders by the Government of India. The service allows an Aadhaar holder to sign in using a one-time password sent to the mobile number used to enroll on Aadhaar. Once inside, residents of India will find a number of digitally signed, legally valid electronic documents waiting for them.

Currently, there are more than 4.6 billion documents issued directly into Digilocker by authorities. These documents range from driver’s licenses, to educational diplomas, to insurance policies. In total, there are currently 1460 institutions signed up as document issuers on Digilocker, 233 are integrated with DigiLocker as requesters who can verify user documents with consent.

DigiLocker is implemented as a government-operated mobile app and web app.

Digilocker Statistics Developer Resources


eSign is a digital signature product built atop Aadhaar. It allows any Aadhaar holder to produce legally valid digital signatures on any document, at any time, using any device. Consent for this signature is obtained through a one-time password sent to the signer’s Aadhaar-linked mobile number.

Presently, eSign is used to streamline workflows for multiple fields including financial services, legal services, healthcare, and more.

In order to gain access to certified eSign in their workflows, application developers must enroll as eSign Application Service Providers (ASPs).