The keyboard is a computer peripheral that can easily break and is an essential computer accessory. Frequent computer use, especially for programmers, means they use it every day. Keyboards can easily develop issues, and when a keyboard malfunctions, not being able to type certain letters or numbers can be particularly frustrating. Here, pcjson.com provides you with an online testing tool to check the functionality of your keyboard keys. Each time you press a key on the keyboard, the corresponding key on the virtual keyboard will highlight in color.