Both the ZKTeco K40 and the ZKTeco F18 are fingerprint machines, both made by ZKTeco, and both are among the most searched attendance devices in Bangladesh. But they are built for two different jobs. Choosing the wrong one usually means paying for a door-control feature you never use, or finding out after installation that your attendance machine cannot open the office door.

K40 vs F18 at a glance

Choose the K40 when:

• You only need to record in and out times — salary, late-coming, overtime.
• Power cuts are common at your site. The K40 has a built-in battery, so staff can keep punching during load-shedding.
• Your team is roughly 1,000 people at one site.
• You want the simplest setup: mount it, connect it to the network or download by USB, done.

Choose the F18 when: 

• The device must also open a door. The F18 drives a third-party electric lock (for example, an EM lock) and accepts an exit button and door sensor.
• You want to know who opened a sensitive room — server room, cash room, store — not just who came to work.
• You have more staff on one door: 3,000 fingerprints and 100,000 logs.
• You are building a bigger system later: Wiegand in/out lets you add a second reader, and RS485 is available for wiring to controllers.

What a complete installation needs

The machine is only part of the job. Plan these with your installer before you buy:

• K40: the device, a network cable (or USB download), and the ZKTeco desktop attendance software. That is usually enough.
• F18: the device, an electric lock (EM lock or bolt lock) with the right bracket, an exit button, an access-control power supply with backup battery, a door sensor (recommended), cabling, and the software.
• Both: a fixed mounting point at chest height, out of direct sunlight and rain.

Software

Both machines work with ZKTeco's desktop software for attendance reports (ZKTime 5.0). The F18 also works with ZKTeco access-control software for door schedules and access levels. If you need attendance from several branches in one place, tell us how many sites and staff you have — we will recommend the right software and device combination rather than a guess.

Three mistakes we see every month

1. Buying an F18 for attendance only. You pay for door-control features and still have to buy a separate power supply. A K40 does that job.

2. Using a K40 to secure a main door. Its access control is basic. For a real door with a lock, exit button, and door sensor, use the F18 or a dedicated access controller.

3. Buying a grey-market unit to save a little money. It may have different firmware, no local warranty, and nobody to take it back when it fails. Check the serial number on ZKTeco's official anti-counterfeiting page before you pay.

Buy genuine, with warranty and support

DigiMark Solution is an Authorized Distributor of ZKTeco in Bangladesh. Every K40 and F18 we sell comes with an official warranty, serial-number traceability, and support from our technical team and RMA centre. Dealers and system integrators get partner pricing and stock from our branches in Dhaka and Chattogram.

Not sure which one fits? Send us your staff counts and whether you need door control — WhatsApp: +880 1979-234342. We reply with the right model and a quotation the same day.