YubiKey 5 NFC vs Feitian BioPass vs SoloKeys Solo 2 — Which Security Key?

Three of the best FIDO2 security keys compared side-by-side. We evaluate protocol support, resident key capacity, NFC, biometrics, open source credentials, and developer ecosystem.

Specs Comparison

FeatureYubiKey 5 NFCFeitian BioPass K26SoloKeys Solo 2
FIDO2 / CTAP2YesYesYes
U2F (CTAP1)YesYesYes
PIV (Smart Card)Yes — PIV + YubiKey PIV ToolNoNo
OpenPGPYes — GPG key storageNoNo
OATH-HOTP/TOTPYes (32 slots)NoNo
Biometric (Fingerprint)No (tap only)Yes — built-in sensorNo (tap only)
NFCYesYesYes
Resident Key Capacity2550+~100
Open SourceNo (proprietary)NoYes — firmware + hardware
USB ConnectorUSB-AUSB-AUSB-A (USB-C available)
Price~$55~$45~$45

Which One for You?

Choose YubiKey 5 NFC if you need maximum protocol support

The only key with PIV, OpenPGP, and OATH. If you use your security key as a smart card for SSH/email encryption in addition to WebAuthn, YubiKey is the only option. 25 resident keys is enough for most users.

Choose Feitian BioPass if you want biometric + NFC at a lower price

The BioPass is the best value biometric key. The fingerprint sensor means you never need to type a PIN — tap and verify with your finger. 50+ resident key capacity. Great for users who want biometric convenience without paying YubiKey Bio prices.

Choose SoloKeys Solo 2 if open source matters to you

The entire firmware is auditable Rust code on an nRF52840. Largest resident key capacity (~100). If you're a security researcher, privacy advocate, or just want verifiable hardware, this is the key. The developer community is excellent.

Related

Best Security Keys — Full buyer's guide | FIDO2 CBOR Attestation Parser — Decode key attestation | FIDO2 & CTAP Protocol Guide