YubiKey 5C NFC - Security Key with USB-C and NFC

Your seed is on steel, your hardware wallet is out of sight – and your email account still hangs on an SMS code that a SIM swap clears out in twenty minutes. That is the gap the YubiKey 5C NFC closes. Plug it into a USB-C port or tap it against your phone, and your login is tied to a piece of hardware nobody can copy remotely.

It stops phishing because the key itself checks which domain it is talking to. A perfect replica of an exchange login gets no answer at all – however convincing it looks and however urgent the email sounded.

What bitcoiners use it for

• Securing accounts at exchanges, brokers and payment services
• Protecting your email inbox – the address every other password reset runs through
• Unlocking password managers: Bitwarden, 1Password, KeePass, Proton Pass
• SSH access to your node or server: the key stays in the chip, not on the disk
• OpenPGP for signed releases and encrypted backups – secp256k1 included
• Computer login on Windows, macOS and Linux

Product details

• Connector: USB-C, plus NFC (ISO 14443-3 Type A)
• Dimensions: 18 × 45 × 3.7 mm
• Weight: 4.1 g
• Material: glass-fibre reinforced plastic, no batteries, no moving parts
• IP68 rated (dust and water resistant), crush resistant up to 25 N·m
• Secure element, serialised, firmware 5.8
• Durability: 100,000+ insertion cycles, 500,000+ write/erase cycles
• Operating 0 to 40 °C, storage −20 to 85 °C
• Manufactured in Sweden

Supported protocols

• FIDO2/WebAuthn with passkeys (100 slots) and FIDO U2F
• Smart card (PIV) with 24 certificate slots
• OpenPGP: RSA up to 4096 bit, P-256, P-384, Ed25519, X25519, secp256k1
• OATH-TOTP and OATH-HOTP (64 slots) via the Yubico Authenticator app
• Yubico OTP, challenge-response, static password

Works with

• Windows, macOS, ChromeOS, Linux
• Android and iPhone: tap over NFC or plug in directly via USB-C

Please note: the YubiKey is not a bitcoin wallet. It holds neither your seed nor any private wallet keys – it protects everything around them. And one piece of practical advice: register two keys with every service, one on your keyring and one in the safe. Register only one and lose it, and you are standing in front of the same locked door as an attacker.

Only USB-A on your machine? Then the YubiKey 5 NFC is the one to get.

Buy the YubiKey 5C NFC at Copiaro – a key on your keyring beats a code by text message. Don't trust, verify.