“The best password is the one users never have to remember”
Key Takeaways
- Passkeys eliminate traditional passwords.
- Built on FIDO2 and WebAuthn standards.
- Resistant to phishing attacks.
- Provide better security and user experience.
- Work across devices through secure synchronization.
- Reduce account recovery and password reset costs.
- Supported by Apple, Google, Microsoft, and major browsers.
Introduction
For decades, usernames and passwords have been the primary method of authentication.
However, passwords introduce major security and usability challenges:
- Weak passwords
- Password reuse
- Credential stuffing attacks
- Phishing attacks
- Password database breaches
- Costly password reset flows
As cyber threats continue to evolve, the industry is moving toward passwordless authentication. One of the most promising solutions is Passkeys.
Instead of asking:
"What password does the user know?"
Passkeys ask:
"Can the user's trusted device prove their identity cryptographically?"
This shift dramatically improves both security and user experience.
Index
- What Are Passkeys?
- Why Passwords Are Failing
- How Passkeys Work
- Core Components
- Passkeys vs Passwords
- Passkeys Architecture
- Registration Flow
- Authentication Flow
- Backend Implementation Example
- Security Benefits
- Enterprise Adoption
- Challenges & Considerations
- Best Practices
- Real-World Example
- Interesting Facts
- Stats
- FAQs
- Conclusion
What Are Passkeys?
A passkey is a cryptographic credential that replaces passwords.
A passkey consists of:
- Public Key
- Private Key
The private key remains securely stored on the user's device and never leaves it.
The public key is stored by the application server.
When authentication occurs:
- Server sends a challenge
- Device signs challenge using private key
- Server verifies signature using public key No password transmission occurs.
Why Passwords Are Failing
Traditional passwords suffer from several issues:
Security Problems
- Password reuse
- Brute force attacks
- Credential stuffing
- Phishing scams
- Database leaks
User Experience Problems
- Forgotten passwords
- Complex password rules
- Frequent resets
- Multiple account management According to industry reports, compromised credentials remain one of the most common causes of security breaches.
How Passkeys Work
Passkeys rely on:
- WebAuthn
- FIDO2
- Public Key Cryptography
High-Level Flow:
User Device
↓
Generate Key Pair
↓
Private Key → Stored Securely
Public Key → Stored by Server
Authentication:
Server Challenge
↓
Device Signs Challenge
↓
Server Verifies Signature
↓
Access Granted
The server never stores sensitive secrets that can be stolen and reused.
Core Components
1. User Device
Examples:
- iPhone
- Android Device
- MacBook
- Windows PC Stores the private key securely.
2. Authenticator
Responsible for:
- Biometric verification
- Key generation
- Challenge signing
Examples:
- Face ID
- Touch ID
- Windows Hello
3. Relying Party (Application)
The application requesting authentication.
Examples:
- Banking App
- SaaS Platform
- E-commerce Website
4. Authentication Server
Stores:
- Public keys
- Credential IDs
- User metadata
- Verifies cryptographic signatures.
Passkeys vs Passwords
Passkeys Architecture
Recommended Architecture
Client Device
↓
Browser (WebAuthn)
↓
Authentication API
↓
Passkey Service
↓
Credential Database
Components:
- Browser
- Authenticator
- Backend API
- Credential Store
Registration Flow
User creates account
↓
Server generates challenge
↓
Browser invokes WebAuthn
↓
Authenticator creates key pair
↓
Public key sent to server
↓
Server stores credential
Example:
Endpoint : POST /register/passkey
Response:
{
"challenge": "randomChallenge",
"rpId": "example.com"
}
Authentication Flow
User clicks "Sign In"
↓
Server generates challenge
↓
Authenticator verifies user
↓
Challenge signed
↓
Signature sent to server
↓
Server validates signature
↓
User authenticated
Example:
Endpoint : POST /login/passkey
{
"credentialId": "...",
"signature": "...",
"clientDataJSON": "..."
}
Backend Implementation Example
Node.js Example
import { generateAuthenticationOptions } from '@simplewebauthn/server';
const options =
generateAuthenticationOptions({
rpID: 'example.com'
});
return options;
Verification:
const verification =
await verifyAuthenticationResponse({
response,
expectedChallenge,
expectedOrigin,
expectedRPID
});
if (verification.verified) {
// Login user
}
Security Benefits
1. Phishing Resistance
Users cannot accidentally reveal a passkey.
The credential works only for the legitimate domain.
2. No Shared Secrets
Servers store public keys only.
Database leaks become significantly less damaging.
3. Strong Cryptography
Uses modern asymmetric cryptography rather than user-generated passwords.
4. Built-in MFA
Something you have:
- Device
Something you are:
- Face ID
- Fingerprint
- This provides MFA-like protection without additional friction.
Enterprise Adoption
Major technology companies have already embraced passkeys.
Examples:
- Apple
- Microsoft
- Amazon
- GitHub
- Shopify Many enterprise identity providers now support passkey-based authentication.
Challenges & Considerations
Device Recovery
Users may lose devices.
Recommended:
- Passkey synchronization
- Recovery methods
- Secondary authenticators
Legacy Systems
Older applications may require:
- Hybrid authentication
- Password fallback
User Education
Many users are unfamiliar with passkeys.
Clear onboarding is essential.
Best Practices
1. Support Multiple Authenticators
Allow users to register multiple devices.
Examples:
- Phone
- Laptop
- Security Key
2. Maintain Recovery Flow
Always provide secure account recovery.
3. Use Trusted Standards
Prefer:
- WebAuthn
- FIDO2 Avoid custom cryptographic implementations.
4. Log Authentication Events
Track:
- Device registrations
- Authentication attempts
- Credential removals
Real-World Example (SaaS Platform)
Scenario:
A project management platform wants passwordless login.
Registration:
- User signs up
- Creates passkey
- Public key stored Login:
- User enters email
- Device prompts Face ID
- Signature generated
- Server verifies
- User logged in No password required.
Interesting Facts
- Passkeys are based on the FIDO2 and WebAuthn standards developed by the FIDO Alliance.
- Private keys never leave the user's device, making passkeys highly resistant to credential theft.
- Major technology companies including Apple Passkeys, Google Passkeys, and Microsoft Passkeys support passkey authentication.
- Passkeys automatically protect users against phishing because credentials are bound to the legitimate website domain.
- The technology behind passkeys originated from the FIDO Alliance's mission to eliminate passwords entirely.
Stats
- According to Verizon Data Breach Investigations Report (DBIR), compromised credentials remain one of the most common causes of data breaches.
- Microsoft Security Research reports that password-based attacks continue to be one of the largest attack vectors on user accounts.
- According to the FIDO Alliance Passkey Research, users experience faster sign-ins and significantly lower account recovery requirements when using passkeys.
- Organizations adopting passwordless authentication often report reduced helpdesk costs related to password resets and account lockouts.
- Passkeys can dramatically reduce the success rate of phishing and credential-stuffing attacks because no reusable secret is transmitted or stored on the server.
FAQs
Q1. Are passkeys more secure than passwords?
Yes. They eliminate phishing, password reuse, and credential stuffing risks.
Q2. Can passkeys replace MFA?
In many cases, yes. Passkeys combine device possession and biometric verification.
Q3. What happens if I lose my device?
You can recover access using synced passkeys, backup devices, or account recovery methods.
Q4. Do passkeys require biometrics?
No. Devices can also use PINs or other local authentication methods.
Q5. Are passkeys supported by browsers?
Yes.
Supported browsers include:
- Chrome
- Safari
- Edge
- Firefox (partial support depending on platform)
Conclusion
Passwords have served the internet for decades, but they introduce significant security and usability challenges.
Passkeys represent the next evolution of authentication by replacing shared secrets with strong cryptographic credentials.
By adopting passkeys, organizations can build authentication systems that are:
- More secure
- Phishing resistant
- Easier to use
- Easier to scale
- Lower maintenance As the industry continues moving toward passwordless authentication, passkeys are rapidly becoming the new standard for secure user identity verification.
"Passwords prove what you know. Passkeys prove who you are through trusted cryptography."
About the Author:Mayank is a web developer at AddWebSolution, building scalable apps with PHP, Node.js & React. Sharing ideas, code, and creativity.
