Password Manager Lab
guides

Passkeys explained: how they work and when to use them

A clear explanation of passkeys (FIDO2/WebAuthn): what they are, why they're phishing-resistant, where they're supported, and how they interact with password managers.

By PML Editorial · · 8 min read

Passkeys are the replacement for passwords that the industry has been building toward for years. In 2026, they’re supported by most major platforms and many high-traffic sites. Here’s what they actually are and when to use them.

What a passkey is

A passkey is a cryptographic key pair: a private key stored on your device and a public key registered with the website. When you log in, the site sends a challenge, your device signs it with the private key, and the site verifies the signature with your public key.

No password is ever sent over the network. There’s nothing for a phishing site to capture.

The underlying standard is FIDO2/WebAuthn. “Passkey” is the consumer-friendly name for a resident credential stored in a FIDO2 authenticator.

Why passkeys are phishing-resistant

A passkey credential is bound to the origin — the exact domain where it was registered. When you registered your Google passkey at accounts.google.com, the origin is cryptographically embedded in the credential.

When an attacker sets up accounts-g00gle.com and tricks you into visiting it, the browser’s WebAuthn implementation checks the origin. It won’t sign a challenge for a domain that doesn’t match the registered origin. The passkey cannot be used on a phishing site — not even by the attacker.

This is the core property that passwords and TOTP codes don’t have. A phishing site can relay your password and TOTP code in real time. It cannot relay a passkey authentication.

Where passkeys are stored

Passkeys can be stored in:

Support in 2026

Sites and services with passkey support:

OS and browser support:

Passkeys vs TOTP 2FA

PasskeysTOTP
Phishing resistantYesNo
Brute-force resistantYesPartially (30s window)
Works offlineYes (device-bound)Yes
Lost device recoveryVia sync/backupBackup codes
Setup complexityLow-mediumLow
Site supportGrowing, not universalWide

If a site offers passkeys: use them. If not: use TOTP over SMS.

Passkeys and password managers

If you store passkeys in your platform authenticator (iCloud Keychain / Google), they’re only usable on that ecosystem’s devices.

Storing passkeys in your password manager (1Password, Bitwarden) decouples them from a single ecosystem. You can use a passkey registered in 1Password on any device where 1Password is installed. This is the right approach if you use mixed platforms.

How to start using passkeys

  1. Check if your password manager supports passkeys — 1Password and Bitwarden do as of 2026.
  2. Register a passkey on Google/Apple ID first — high-value targets, well-implemented.
  3. For each site that offers passkeys: register one and delete the password entry.
  4. Keep your old password as a fallback until you’re confident the passkey flow works on all your devices.

The transition is gradual. Don’t delete passwords for sites until you’ve verified passkey login works end-to-end on your primary devices.

What passkeys don’t protect against

Passkeys are a significant improvement. They’re not a silver bullet.

#passkeys #fido2 #webauthn #2fa #fundamentals

Related

Comments