The YubiKey 5 Nano FIPS is a hardware security key designed for multi-factor authentication in government and regulated organizations. The device is FIPS 140-2 validated at Overall Level 2 with Physical Security Level 3 certification. It connects via USB-A interface and features a nano form-factor intended to remain inserted in the device. The security key supports multiple authentication protocols including FIDO2/WebAuthn for hardware-bound passkeys, FIDO U2F, Yubico OTP, OATH-TOTP, OATH-HOTP, Smart card (PIV), and OpenPGP. It provides 25 passkey slots, 32 OATH slots, 24 PIV certificates, and 2 OTP seeds. The device supports RSA cryptography (1024-4096 bits for OpenPGP, 1024-2048 bits for PIV) and ECC (P-256, P-384), along with modern curves including Ed25519, X25519, secp256k1, and various brainpool curves. It operates as an HID keyboard, CCID smart card, and FIDO HID device. The YubiKey 5 Nano FIPS is manufactured in Sweden and programmed in the USA. It features IP68 water and dust resistance, supports over 100,000 USB insertion cycles, and has a mean time between failure of over 100 years. The device requires no batteries or network connectivity and operates across Windows, macOS, Chrome OS, and Linux platforms with Chrome and Edge browser support. This product is sold in trays of 50 units and runs firmware version 5.4.