The $100 Fingerprint Reader Tested

Want to add biometrics but avoid spending nearly $1,000 per door for it?

When it comes to fingerprint readers, there are lots of options that all claim to perform the same. However, the ZKTeco F7 Fingerprint Reader [link no longer available] is the least expensive Wiegand/Fingerprint Reader on Amazon, available for ~$80 from several sellers, and generally less than $120 from any of them.

While this unit is commonly rebranded as an OEM and is resold under countless model numbers, it is far less expensive that premium brand offerings.

[Note: this is our first test in a series on fingerprint readers, which will also include tests on BioScrypt, Morpho and Superma this summer.]

Below is the first of 4 videos inside this report that show our test findings:

The key findings of our test include:

• Stand Alone Unit (Reader/Controller): Good. While hardware design is surprisingly solid, the lack of central management software means the unit is best for single door or very small systems.
• Wiegand Reader (Paired with 3rd Party Controller): Bad. Despite being an option, we found the unit unusable with 3rd party controllers.
• Stability: Great. We experienced no lockups, hangs, or lags in reading prints or unlocking locks.
• Sensor Accuracy: We enrolled one finger three times from three subjects each. After 100 consecutive reads from those subjects (33 reads from each subject), the unit measured 87 out of 100 correct reads, with 13 sporadic 'false negative' reads with no subject generating more errors. There were zero 'false positive' tests performed.
• Software (English Version): Complex. The included software is not intuitive, poorly translated in some screens, and confusing function labels are used throughout.
• Always On: We noticed the unit never 'hibernates' the sensor and instead keeps the unit constantly on. While this means high availability and quick response, this also means high power consumption and presumably shorter sensor service life. While the additional electricity cost is trivial, it will be higher than many competitive units, and the bright light of the sensor could be a source of light pollution in some areas.

We examine each of these aspects in the sections that follow.

Product Features

Here are the feature claims or characteristics we found most important:

• Wiegand Output: The unit claims it can be used in 'reader only' configuration attached to other controllers via wiegand, RS232, or RS485 communication.  However, we had no success in getting this feature reliably working.
• IP, but not PoE: The unit can be configured via network, but must be externally powered by a linear 12 VDC @ 3A power supply.
• Software Needed: Additionally, configuration clients must be downloaded to tweak unit settings. The unit does not come with a 'web server' application that permits direct interface.
• Sensor Type: The F7 is equipped with an optical sensor that includes 'liveness' checking for heartbeats. The quality of reads were good, and errors under optimal conditions were within the tolerance range of most applications.
• Local Enrollment: The unit's sensor can be used to add fingerprints to the user library, instead of requiring a separate USB connected sensor required by some units.

Overall, especially for a budget price reader, the mix of options and build quality of components is good. The housing is well molded and all components feel 'quality' with bright display, firm tactile button keypad, and steel mounting bracket.

Performance Summary

Watch the video below where we highlight the problems with knowing how exactly to use the unit due to lack of prompts or instructions:

In summary, without explicit instructions displayed like 'Enter Code' or 'Place Finger on Sensor', unfamiliar users may find themselves unable to correctly use the device to open doors. While the unit supports both '1:1' and '1:N' type scanning, which option is configured is not clear on the reader's LCD and only placing your finger on the sensor may be pointless in opening the door even if valid in the system.

The Showstopper

While the unit claims to work in either 'Standalone' OR '3rd Party' modes, we found it usable only when it worked with its own controller. 

When door strikes and position switches were directly attached to the unit, they unlocked/relocked reliably. Even advanced features like 'antipassback' are supported in standalone mode, and the unit did not fail to perform in this configuration.

However, when paired with the Axis A1001, the reader did not work as advertised.  While the wiegand interface indeed showed live data was being pushed from the reader to controller, that data was not formatted correctly as defined by the manuals, or the physical wiring needed to differ from how it was described in the installation guide. 

A problem not addressed by any documentation was that wiegand values appeared to change with each read, even when the same finger is used. This screenshot illustrates examples:

This most likely is a misconfiguration issue, but with no clear root cause and no clear tech support escalation path, this would be a big problem in the field.

Configuration

Finally, both the orientation and language of the configuration application was difficult to understand. This video offers examples of how the unit is configured by the software client:

All configuration must be done either via this client, or by navigating menu options on the unit's keypad. There is no 'web server' GUI for onboard configuration changes.

All instructions and client were furnished with the unit on a CD, and while the disk is full of hundred of files, only very few actually pertain to the F7 model, with the rest being relevant to other units. There are four different client applications, and the only sure way of knowing which version to use with the F7 is to compare screenshots in the installation guide with the client being referenced.

The Verdict

While this unit is indeed inexpensive, significant cost will be spent trying to get it working with most access systems. We do not recommend using it with 3rd party controllers.

The unit may be useful for controlling a token door, but with the kludgy management software and a steep learning curve to become familiar, even single-door options compatible with Edge Solo controllers may prove less frustrating to work with.

Shootout Coming

We will continue testing fingerprint readers, culminating in a 'Biometric Shootout' report later this year. We will test mainstream offerings from Morpho, Supreme, and HID to compare against this unit.