A lot of keyboards these days, particularly on laptops, are designed to be as compact and cheap to make as possible. On the cost-savings front, they use squishy membranes to detect key presses, but those have a terrible feel. To keep things compact, they often omit “superfluous” keys such as the number pad. But those keys are important for people who do real work on their computers. If you’ve been missing those in your life, Mattia Dal Ben has designed an open source macropad that you can build yourself.
YamPAD (Yet Another Mechanical numPAD) is, as the name suggests, a clicky mechanical keypad designed to be used as a number pad. It uses Cherry MX-style key switches, so you can customize it for whatever tactile feel you prefer. In total, there are 18 keys arranged in a typical number pad layout. The only difference is that the bottom row has four keys, instead of the normal three. That allows you to use the four keys on the bottom two rows as navigational direction (arrow) keys if needed. Key layouts can be swapped on the fly, so you can use the keypad for whatever functions you like. There are even RGB LEDs and an OLED display to provide feedback.
The controller for the YamPAD is an Arduino Pro Micro, which shows up on your computer as a USB HID (Human Interface Device) once you flash the corresponding code. This does require a custom PCB, but the schematics and Gerber files are provided so you can have one made. Once you have the hardware setup, you can 3D print a case to keep everything tidy. If you’ve been looking for a supplementary keypad to improve your productivity, YamPAD is one of the most fully-featured designs we’ve seen yet.