The $68 YubiKey 5C Nano is a compact hardware security key that supports a wide range of authentication protocols, passkey storage, and smooth integration with leading business platforms. Its tiny form factor means you can leave it plugged into your device without it getting in the way, making it ideal for professionals who need constant, high-level security. Thanks to its robust feature set and reliable multi-factor authentication (MFA) support, it earns our Editors' Choice award for advanced security keys. That said, for casual users seeking essential protection at a lower cost, the $29 Yubico Security Key C NFC is a better fit.

Pricing and Perks: Expensive, But Worth It

You're primarily paying for the petite form factor, as the YubiKey 5C Nano costs $68 and shares the feature set with the YubiKey 5C NFC. The keys support larger RSA keys and X25519 key types, which are particularly useful for individuals in business settings.

The YubiKey 5C Nano supports the following authentication protocols: WebAuthn, FIDO2 CTAP1, FIDO2 CTAP2, Universal 2nd Factor (U2F), Smart card (PIV-compatible), Yubico OTP, OATH – HOTP (Event), OATH – TOTP (Time), OpenPGP, and Secure Static Passwords. As mentioned above, the less-expensive Yubico Security Key NFC—and some competitors—only support tap-to-authenticate MFA.

The Nano keys are compatible with various business software solutions, including AWS Identity and Access Management (IAM), Duo Security, ForgeRock, Idaptive, Microsoft Azure AD, Okta, OneLogin, and Ping Identity. You can also use a hardware security key to log in to some of your social media and email accounts. Apple, Google, Meta, and Microsoft all support account sign-in with a hardware security key.

The Yubico Security Key C NFC offers less versatility than the 5-series keys, but at $29, it's an inexpensive introduction to authentication with security keys. The Security Key devices support FIDO2 CTAP1, FIDO2 CTAP2, Universal 2nd Factor (U2F), and WebAuthn protocols.

Yubico's YubiKey Nano keys offer diverse storage options, including 64 OATH seeds, 24 PIV certificates, and 2 OTP seeds, as well as room for up to 100 passkeys. If you need more passkey storage and fewer authentication options, Google's Titan Key can hold up to 250 passkeys and supports the same protocols as the Yubico Security Key C NFC.

Features: Tiny, Convenient Form Factor

The YubiKey 5C Nano is part of the YubiKey 5 series, designed for experienced security key users who require keys that offer more versatility than the budget-friendly Yubico Security Key line. The keys in this series all communicate differently with your devices. The 5Ci, for instance, has Apple Lightning and USB-C connectors. The 5 NFC has either a USB-A or USB-C connector and can communicate wirelessly via NFC. The Nano version also has USB-A and USB-C versions. For this review, I tested the USB-C key.

(Credit: Kim Key)

Connection differences aside, the two Nano keys look very similar, and both boast diminutive dimensions, each smaller than a quarter. The Nano keys are so small that they don't have room for the round metallic Y symbol we've come to associate with Yubico's devices. Instead, they have a tiny gold metal button that users tap to authenticate their identity.

There is no need to carry around a key ring for this hardware security key. The YubiKey Nano keys are small enough to stay plugged into your desktop or laptop. I found that the USB-C version blended well with the face of my Windows desktop tower.

(Credit: Kim Key)

Hands-on Test Results: Easy to Use

Using a hardware security key is usually straightforward, but the Nano simplifies the process even further by eliminating a step. You can keep it plugged into your desktop, laptop, or even a mobile device and just tap it whenever a website prompts you to do so. Yubico offers helpful videos on its website to guide new users through enrolling their hardware security keys on various platforms and websites.

(Credit: Proton/PCMag)

I linked the YubiKey 5C Nano to a Proton Mail account by visiting my account settings section, following the on-screen prompts, and tapping the top of the key as instructed. The next time I logged into the Proton Mail account, it requested a touch confirmation via the security key to verify my identity. Overall, the key worked as advertised.

(Credit: Kim Key)

For the next test, I successfully added the YubiKey 5C Nano to a Google account on my Samsung phone. I just plugged the key into the phone's USB-C port and tapped it when prompted. I found that YubiKey 5C Nano keys are small and unobtrusive enough to live in a mobile device's charging port indefinitely, which is a plus.