Passkeys, security keys, and the parts nobody explains
Passkeys work brilliantly until they don't. When they fail, the useful question is not "what is a passkey" but "where is my credential actually stored, and what happens if this device is gone".
Margelab publishes short, practical write-ups for people who are already using passkeys — or who have been told to, and are now stuck. Every page is written to be checkable: where we are not certain about a vendor's behaviour, we tell you how to confirm it yourself rather than asserting it.
Start here
- Passkey troubleshooting index Symptom first: the prompt never appeared, login still fails, it works on one device only.
- Passkey backup and recovery, explained What "backup" actually means for a passkey, and how to make sure a lost phone is not a lost account.
- Lost your phone What survives a lost device, what does not, and what to do in the first hour.
Troubleshooting
- Passkey not working A symptom taxonomy, then an ordered path through it.
- Passkey saved but login still fails Saved is not the same as registered — the four gaps that cause this.
- iPhone: iCloud Keychain vs a password manager Which layer wins by default, and how to find out where a given passkey lives.
- Android and phone-number sign-in Why number-linked accounts and passkeys interact badly.
- Old devices and browsers The three independent layers that decide whether you get a passkey prompt at all.
Scenarios
- Your employer forced passkeys through SSO Keeping a work identity separate from a personal one, deliberately.
- Shared and family computers The one mistake that hands a synced passkey to everyone using that profile.
- Passkeys or a password manager first Why it is not either/or, and the order that avoids a lockout.
Choosing software
- Which password managers actually support passkeys The three questions that separate the products, and how to verify each claim in a trial.
- Password managers with real passkey recovery Has passkeys, and can recover your passkeys, are different claims.
Margelab is an independent publication. We are not affiliated with, endorsed by, or sponsored by any device, browser, operating system, or password-manager vendor named on this page. Product names are used for identification and commentary only.
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Last updated: 2026-10-16