What is passwordless authentication?
Passwordless authentication is an authentication method that allows users to sign in to computer systems without entering (or remembering) a password or any other knowledge-based secret.
For example, when you unlock your smartphone using your fingerprint or face recognition, or when you receive a one-time code via SMS to log into your email account - these are all common passwordless authentication methods we use in our daily lives.
What are the types of passwordless authentication?
There are several common types of passwordless authentication that we encounter in our daily lives:
Biometric authentication
Biometric authentication leverages our unique physical characteristics for identity verification, primarily through fingerprint scanning, face recognition, and iris scanning. We encounter these in everyday situations:
- Unlocking your iPhone with Face ID while buying coffee
- Logging into your banking app with your fingerprint
- Accessing secure facilities using iris scanners
Magic links
Magic links are special one-time use links delivered to your email, offering a seamless authentication experience. You’ll find them in many popular services:
- Clicking a “Sign in” link from Slack in your email
- Medium’s “Sign in with email” option that sends you a login link
- Notion’s email-based authentication system
Checkout Magic link for more details.
One-Time codes (OTP)
One-time codes, typically delivered via SMS or email, represent one of the most widespread passwordless methods:
- Receiving a 6-digit code to log into your Google account
- Getting a verification code for online banking transactions
- Using an authenticator app like Google Authenticator
Checkout One-time password (OTP) for more details.
Passkeys
Passkeys are FIDO-based secure alternatives to traditional passwords that use advanced cryptography to protect your accounts from phishing attacks. Here’s how they work:
- Unique per service: When you register for a service, your device creates a unique passkey linked to that specific service’s domain
- Device-based: Passkeys are typically stored in hardware security modules, either built into your devices or as separate security keys
- Public-private key pairs: The device securely stores the private key while sharing the public key with the service. These cryptographic key pairs are what we call passkeys
- Hardware security: Many passkeys are protected by dedicated hardware security modules, making them extremely difficult to compromise
- Cross-device sync: Passkeys can be securely synced across devices using cloud storage (e.g., Apple’s iCloud Keychain or Google Password Manager)
Common usage scenarios:
- Using a USB security key to access your work laptop
- Tapping your phone (as a security key) to log into your Google account
- Connecting a hardware security key to access highly secure systems
Checkout Passkey for more details.
Why use passwordless authentication?
For decades, passwords have been the default method for authentication. Even today, most of our online accounts still rely on passwords. However, this traditional approach is facing increasing challenges, making us question: why should we use passwordless authentication?
Passwords are not secure enough
When a company experiences a data breach, millions of passwords can be exposed at once. Attackers can easily exploit these passwords through automated tools, especially since many users reuse their passwords across different services. For instance, if an attacker obtains a user’s password from a compromised gaming website, they might gain access to that person’s email or banking accounts using the same credentials.
Check out this blog to learn How are your passwords cracked? .
Passwords are difficult to use and manage
Think about managing your online accounts: you have dozens of accounts across different websites and services, each with its own password requirements. Even if you try to use a consistent password, different password policies force you to add special characters, numbers, or make other variations. One website requires at least one special character, another doesn’t allow certain symbols, and a third one demands a minimum of 12 characters.
When you try to log in, you can’t remember which variation you used for this particular site. Was it the one with the exclamation mark at the end? Or the one with the ”@” symbol? After several failed attempts, you’re locked out and have to go through yet another time-consuming password reset process.
This frustrating scenario plays out millions of times daily across organizations, leading to constant password resets, wasted time, and reduced productivity.
Passwordless authentication is more secure than passwords
Imagine instead using your fingerprint or face recognition to access all your work applications. Since these biometric factors can’t be stolen or guessed like passwords, even if an attacker breaches the company’s database, they can’t use this information to impersonate users. Additionally, passwordless methods like security keys provide protection against phishing attacks, as they verify both the user and the website’s authenticity.
Passwordless authentication user-friendly
With passwordless authentication, accessing your accounts becomes as simple as unlocking your smartphone.
For example, when you receive a push notification on your phone to approve a login attempt, you can authenticate with just a tap or a quick glance at your device. This seamless experience eliminates the cognitive burden of remembering multiple passwords while maintaining high security standards.
How does passwordless authentication work?
Authentication generally relies on three types of factors:
- Something the user knows: like passwords or PINs
- Something the user has: like physical devices or tokens
- Something the user is: like biometric traits.
Passwordless authentication moves away from the traditional “something you know” approach, focusing instead on the other two factors.
When using “something you have”, the authentication process typically starts with your email address or phone number. Imagine you’re logging into your bank account - instead of typing a password, you might receive a one-time code via SMS or email. Or perhaps you’ve set up an authentication app on your phone that generates these codes automatically. Some services even send push notifications to your phone, allowing you to simply tap “Approve” to log in. For higher security needs, you might use a physical security key that plugs into your device, similar to inserting a digital key.
The “something you are” approach is even more straightforward and is probably already familiar to you. When you unlock your smartphone with your fingerprint or by looking at the screen for face recognition, you’re using biometric authentication. Some systems also use voice recognition, where speaking a specific phrase can verify your identity. These biometric factors are unique to you and are processed securely on your device.
What’s the difference between passwordless authentication and multi-factor authentication (MFA)?
Passwordless authentication and Multi-factor authentication (MFA) are sometimes mentioned in similar contexts. Therefore, it is necessary to define these two terms separately and understand the difference between them:
- Passwordless authentication replaces password-based authentication with other factors.
- MFA refers to using two or more authentication factors to verify a user’s identity.
“Factors” are seriously the three different types of authorization information we mentioned earlier. For example, if a user only uses an email address + OTP during authentication, this is a factor associated with “something the user has”, and we can consider the user’s authentication to be passwordless.
Common MFA implementations include using a second (passwordless) authentication factor to enhance a password, but MFA can also be completely passwordless. For example, an application could use a fingerprint as the first authentication factor and email address + OTP as the second authentication factor.
What’s the difference between passwordless and SSO?
Single sign-on (SSO) (SSO) and passwordless authentication are two distinct concepts in identity management:
- SSO is about centralizing user authentication, allowing users to access multiple applications with a single login
- Passwordless authentication focuses on how users prove their identity without using passwords
While they serve different purposes, they can work together.
For example, an SSO system can use passwordless methods (like biometrics or security keys) for authentication. This combination provides both the convenience of single sign-on and the security benefits of passwordless authentication.