Card, PIN, fingerprint, face or mobile: access control readers compared.

Doors differ in risk, and so should their credentials.

Proximity and smart cards

Convenient and inexpensive. Older 125 kHz cards are easy to clone; modern encrypted smart cards at 13.56 MHz are much stronger. Use secure formats for new installations.

PIN codes

Low cost and no card to lose, but codes get shared. Best combined with a card for sensitive areas.

Fingerprint

Ties access to a person. Works well in most offices. Dry, worn or dirty fingers cause failures, and hygiene concerns affect public use.

Face recognition

Contactless and fast, useful at turnstiles and entrances with many users. It depends on camera quality and lighting, and raises privacy questions that need clear policy and consent.

Mobile credentials

Phones act as keys over Bluetooth or NFC. Easy to issue and revoke remotely, and good for visitors and contractors. Needs staff to carry and charge their phones.

Multi-factor at the door

For server rooms, vaults and laboratories, combine two factors: card plus PIN, or card plus biometric.

Beyond the reader

The controller, door hardware, power supply, fail-safe or fail-secure choice and fire-alarm release matter as much as the reader. A strong reader on a weak door is no protection.

Choose by zone

Low-risk areas: card or mobile. Sensitive areas: two factors. Visitors: temporary mobile or printed passes with limited rights.