Fingerprint
Fingerprint entry is the fastest method for a fixed group of regular users: no code to remember, nothing to carry, nothing to share by accident. The trade-off is read reliability, which depends on the sensor type and the condition of the finger presented to it.
Sensor types
What to check
- Enrolment capacity - how many prints the lock stores. Entry-level models may hold 20; commercial models several hundred.
- Prints per user - enrol at least two fingers per person, ideally on different hands.
- Fallback method - a keypad or credential for when a print will not read. A fingerprint-only lock is a poor idea.
- Lockout behaviour - what happens after repeated failed reads, and how long the lockout lasts.
- Sensor position - a reader in the handle or on a vertical face sheds water better than one facing upward.
Read failures are almost always enrolment quality, not sensor failure. Enrol with a clean, dry finger, take several captures at slightly different angles, and re-enrol anyone whose reads become inconsistent. Fingerprint enrolment tips.
Where fingerprint suits, and where it does not
- Suits - family homes, small offices, gyms, anywhere the same people use the door daily.
- Suits - accessibility applications where carrying and manipulating a key is difficult.
- Poor fit - short-stay rentals and rotating guests, where you cannot enrol people in advance.
- Poor fit - trades and manual work environments, where fingers are worn, wet or dirty.
- Poor fit - doors used by young children, whose prints change as they grow.
Related categories
Palm and Face Recognition · PIN Code Smart Locks · Smart Locks With Backup Key · Smart Padlocks
Common questions
Why does my fingerprint stop reading in wet weather?
Water on the sensor or the finger disrupts the ridge pattern the sensor is measuring, particularly on capacitive readers. Dry the finger and the window. If it recurs constantly, the reader position may be taking direct rain and a sheltered mounting or different lock is the fix.
Water on the sensor or the finger disrupts the ridge pattern the sensor is measuring, particularly on capacitive readers. Dry the finger and the window. If it recurs constantly, the reader position may be taking direct rain and a sheltered mounting or different lock is the fix.
Are fingerprints stored as images?
No. Locks store a mathematical template derived from the print, not a photograph, and the template cannot be reversed back into a usable fingerprint. The template is held on the lock itself on most models.
No. Locks store a mathematical template derived from the print, not a photograph, and the template cannot be reversed back into a usable fingerprint. The template is held on the lock itself on most models.
How many fingerprints can it hold?
It varies widely by model, from around 20 on entry-level locks to several hundred on commercial platforms. Check the figure on the product page and allow two prints per person.
It varies widely by model, from around 20 on entry-level locks to several hundred on commercial platforms. Check the figure on the product page and allow two prints per person.
Can children use fingerprint locks?
Young children's prints are small and change as they grow, so reads become unreliable and re-enrolment is needed periodically. A PIN is usually the better option for that user group.
Young children's prints are small and change as they grow, so reads become unreliable and re-enrolment is needed periodically. A PIN is usually the better option for that user group.
Guides and reference
Ch 03 - Fingerprint access · Ch 13 - Smart lock FAQ · Fingerprint enrolment tips