Passkey vs Password: Is It Time to Switch?

Passkeys are a more secure and convenient replacement for passwords, and yes, you should switch to them wherever they are offered. They work by using cryptographic key pairs stored on your device, eliminating the need to type or remember a password. This article explains how passkeys work, their benefits and limitations, and how to start using them today.

Formula

The password entropy is calculated as: Entropy = length × log₂(character set size). This gives the number of bits of uncertainty in the password. The time to crack is then estimated as Time = 2^entropy / (guesses per second × seconds per year), assuming an attacker can make 1 trillion (10¹²) guesses per second. This is a rough upper bound; real-world cracking often uses dictionary attacks, which are much faster.

Worked Example

Using the default values: a 12-character password from a 94-character set (uppercase, lowercase, digits, symbols).

1. Entropy = 12 × log₂(94) = 12 × 6.5546 = 78.65 bits
2. Time to crack = 2^78.65 / (10¹² × 31,536,000) ≈ 4.8 × 10²³ / 3.15 × 10¹⁹ ≈ 15,238 years

The calculator shows 15,238 years, which is the same result. This illustrates why a long, random password is still strong, but passkeys are even stronger because they use 256-bit keys.

What Exactly Is a Passkey?

A passkey is a digital credential that replaces passwords. It is based on public-key cryptography: your device generates a unique key pair – a private key stored securely on your device (in a secure enclave or TPM) and a public key stored on the website’s server. When you log in, the website sends a challenge, your device signs it with your private key, and the server verifies it with your public key. Your private key never leaves your device, so it cannot be stolen in a data breach.

Passkeys are standardized by the FIDO Alliance and the W3C WebAuthn specification. They work across platforms: Apple, Google, and Microsoft have all adopted them, so you can use passkeys on iOS, Android, Windows, and macOS. They also sync across devices via cloud services like iCloud Keychain, Google Password Manager, or Microsoft Authenticator.

Why Are Passkeys More Secure Than Passwords?

Passwords have fundamental flaws that passkeys solve:

• Phishing resistance: Passkeys are bound to the specific website’s origin, so a fake site cannot trick your device into signing a challenge.
• No password reuse: Each passkey is unique to the site, so a breach on one site doesn’t affect others.
• No credential theft: The private key never leaves your device, so server-side breaches only expose public keys, which are useless without the private key.
• No weak passwords: You don’t choose a passkey; it is generated with high entropy (256-bit keys), making brute-force attacks infeasible.

In contrast, passwords can be phished, reused, guessed, or stolen from databases. Even with two-factor authentication (2FA), attackers can bypass it with SIM-swapping or man-in-the-middle attacks. Passkeys eliminate these vectors.

How to Start Using Passkeys

Switching is straightforward, but the steps vary by platform. Here’s a general guide:

1. Check if a website supports passkeys. Look for a “Passkey” or “Security Key” option in account settings or during login.
2. On your device, ensure you have a passkey manager enabled: Apple iCloud Keychain (iOS/macOS), Google Password Manager (Android/Chrome), or Microsoft Authenticator (Windows).
3. When prompted, create a passkey. You may be asked to authenticate with your fingerprint, face, or PIN – this is just to unlock your device, not the passkey itself.
4. Test the passkey by logging out and back in. You should be able to log in with just your biometric or device PIN.
5. Keep your password as a fallback until you’re confident the passkey works, then remove the password if the site allows.

For example, on an iPhone, go to Settings > Passwords, and you’ll see which accounts have passkeys. On a Windows PC, you can manage passkeys in Windows Hello settings. Many popular sites like Google, Amazon, and PayPal already offer passkeys.

Common Problems and Misconceptions

One common misconception is that passkeys are tied to a single device and you’ll be locked out if you lose it. In reality, passkeys sync across your devices via your cloud account, and you can also use a phone as a roaming authenticator for a new device. If you lose all devices, you can recover your account using backup methods like recovery codes.

Another issue is cross-platform compatibility. While passkeys are standardized, some sites only support them on certain browsers or devices. For example, a site may support passkeys on iOS but not on Android. This is a temporary transition phase; the industry is moving toward full interoperability.

Some users worry about privacy: does the website know which device you’re using? The public key is unique to your device, but it is not linked to your identity beyond your account. However, your cloud provider (Apple, Google, Microsoft) can see which sites you use passkeys for, similar to how they see your passwords today.

Passkeys vs. Password Managers

Password managers are still useful in the transition. They can store your existing passwords and also generate and store passkeys. In fact, most password managers (like 1Password, Dashlane, Bitwarden) now support passkeys. The difference is that a password manager stores your private key in its vault, whereas a platform passkey manager stores it in the device’s secure enclave. Both are secure, but platform managers are more integrated with the OS.

You might wonder: “Should I use a separate password manager or the built-in one?” It depends on your ecosystem. If you’re all-in on Apple, use iCloud Keychain. If you use multiple operating systems, a cross-platform manager like 1Password might be better. The key is to pick one and be consistent.

Security and Recovery

Passkeys are not immune to all attacks. If someone gains physical access to your unlocked device, they can use your passkeys. That’s why you should always lock your device with a strong PIN or biometric. Also, if your cloud account is compromised, an attacker could potentially access your synced passkeys. So it’s crucial to enable two-factor authentication on your Apple, Google, or Microsoft account.

For recovery, always set up backup methods: recovery codes, a secondary email, or a trusted phone number. When you create a passkey, the site may give you a recovery code – store it safely. If you lose access to your passkey, you can use the recovery code to regain access.

Frequently Asked Questions

Can passkeys be used on multiple devices?

Yes, passkeys sync across your devices via your cloud account. For example, if you create a passkey on your iPhone, it will appear on your iPad and Mac as long as you’re signed into the same iCloud account. You can also use a passkey from your phone to log into a new device by scanning a QR code.

What if I lose my phone?

If you lose your phone, you can still access your passkeys on other devices that are signed into your cloud account. If you have no other devices, you can use recovery codes provided by the website, or contact the site’s support to verify your identity. Always set up recovery options in advance.

Are passkeys the same as two-factor authentication?

No, passkeys are a replacement for passwords, not an additional factor. They are inherently multi-factor because they require something you have (the device) and something you are (biometric) or know (PIN). So they provide stronger security than a password alone, but they are not the same as adding a second factor to a password.

Can I still use passwords if I want?

Yes, most sites that support passkeys still allow you to use your password as a fallback. However, the goal is to eventually phase out passwords. It’s best to start using passkeys where available to reduce your reliance on passwords.

Do passkeys work with all websites?

Not yet. Passkey support is growing, but many sites still only offer passwords. You can check a site’s login options to see if “Passkey” or “Security Key” is listed. The FIDO Alliance maintains a directory of passkey-supporting sites, but it’s not exhaustive.

Are passkeys more secure than a password manager with 2FA?

Generally, yes. Passkeys are phishing-resistant and cannot be stolen from a server. A password manager with 2FA is still vulnerable to phishing and SIM-swapping. However, both are much better than passwords alone. The main advantage of passkeys is that they are easier to use and protect against a wider range of attacks.

Related

• Botnet Attacks via Routers & IoT Devices
• Mortal Shell 2: How to Farm Glimpse Fast
• GST on Smartphones & Electronics: Reduced?

in t | Time to crack (years) | years | 10 | 0.0001 | 1000
in p | Password length (characters) | - | 12 | 1 | 100
in c | Character set size | - | 94 | 10 | 200
out entropy | Entropy (bits) | bits | p * log2(c) | 2
out crack_time | Time to crack (years) | years | (2^entropy) / (1e12 * 60 * 60 * 24 * 365) | 2