What Is a Passkey?

A Passkey is a safer and more convenient way to sign in without using a traditional password. In simple terms, it lets you verify your identity through your phone, computer, or hardware security device — for example, by using your fingerprint, face recognition, device lock screen password, PIN, or hardware security key to sign in to apps and websites.

Compared with traditional passwords, Passkeys do not require users to remember complex passwords or reuse the same password across different platforms. This helps reduce risks such as weak passwords, password leaks, credential stuffing, and phishing websites.

Note: Passkey availability may vary depending on your phone model, system version, browser, credential manager, or manufacturer support. If your device does not currently support Passkeys, you may not be able to create or use a Passkey account. Please follow the actual in-app instructions or contact your device manufacturer for details.

How does a Passkey work?

Passkeys are based on public-key cryptography. When you create a Passkey for an app or website, your device generates a key pair: a public key and a private key.

The public key is stored on the app or website server and is used to verify your identity. The private key is stored on your phone, computer, credential manager, secure chip, or hardware security device, and is never sent to the app or website.

When you sign in with a Passkey, the app or website sends a verification request to your device. After you confirm with your fingerprint, face recognition, device password, PIN, or hardware device, your device signs the request with the private key. The server then uses the public key to verify the signature. Once verified, you can complete the sign-in process.

In other words, your identity is verified using the private key stored on your device, rather than a password you type in.

What is the relationship between Passkeys and fingerprint or face recognition?

Many people think of Passkeys as “fingerprint sign-in” or “face sign-in,” but that is not entirely accurate.

Fingerprint, face recognition, or device PIN is only used to unlock the Passkey private key stored locally on your device. Apps and websites do not receive your fingerprint or face data, nor do they directly use these biometric details to verify your account.

You can think of fingerprint, face recognition, or PIN as the way to “unlock the key,” while the Passkey is the actual “key” used for sign-in verification.

What is a hardware Passkey?

In addition to Passkeys stored on phones, computers, or credential managers, there is also a more independent form: hardware Passkeys.

A hardware Passkey usually refers to a hardware security key or hardware authenticator that supports FIDO2 / WebAuthn standards. Unlike Passkeys stored on phones or computers, the private key of a hardware Passkey is usually stored only inside the hardware device and cannot be exported to a computer, phone, or cloud account.

Take imKey Pass S6 as an example. It is a hardware Passkey with fingerprint verification, designed based on the FIDO2 standard. It can be used with websites and apps that support Passkey / security key sign-in. When you use imKey Pass S6 to sign in to an account, you need to connect the device to your computer or phone and confirm the operation with your fingerprint, PIN, or other supported method. The device completes signature verification locally, while the website or app only receives the verification result and does not obtain the private key used for sign-in verification.

Therefore, hardware Passkeys such as imKey Pass S6 are more like independent physical keys. They are suitable for users who have higher account security requirements and want to reduce reliance on cloud-based synchronization.

Is a Passkey the same as a wallet private key or mnemonic phrase?

No.

A Passkey is usually used to prove that “you are the person signing in or performing account-level identity verification,” while a wallet private key and mnemonic phrase represent control over on-chain assets.

A hardware Passkey is also not the same as a hardware wallet. A hardware Passkey is mainly used for account sign-in and identity verification, while a hardware wallet is mainly used to generate and store wallet private keys and sign on-chain transactions locally. Both can improve security, but they protect different things and are used in different scenarios.

Therefore, using a Passkey does not mean you can ignore wallet security. You should still carefully protect your mnemonic phrase, private key, devices, transaction signing details, and approval risks.

What should you keep in mind when using a Passkey?

First, protect your phone, computer, or hardware security device. Do not share your device password, system account password, credential manager account, or hardware device PIN with anyone.

Second, after enabling Passkeys, it is recommended to set up a backup device, backup Passkey, backup security key, or account recovery method in advance, so you can avoid losing access if your device is lost.

Finally, although Passkeys can reduce the risk of password phishing, you should still stay alert to fake websites, fake apps, and malicious links. In Web3, sign-in verification and on-chain transaction signing are two different things. Before every signature or approval, carefully check the transaction details, target website, and contract information.

Summary

A Passkey is a passwordless sign-in method based on public-key cryptography. It allows users to sign in with a fingerprint, face recognition, device password, PIN, or hardware security device, while reducing the risks of password leaks, password reuse, and phishing.

If you want to further improve account security, you can also choose a hardware Passkey such as imKey Pass S6, which stores the private key used for sign-in verification in an independent hardware device.

However, passkeys are not a complete security solution. Whether you use a Passkey on your phone or an independent hardware Passkey, you still need to protect your devices and account recovery methods, and stay cautious when dealing with wallet assets, on-chain signatures, and contract approvals.