Key formation techniques are described. In one or more implementations, an input device includes a key assembly including a plurality of keys that are usable to initiate respective inputs for a computing device, a connection portion configured to be removably connected to the computing device physically and communicatively to communicate signals generated by the plurality of keys to the computing device, and an outer layer that is configured to cover the plurality of keys of the key assembly, the outer layer having a plurality of areas that are embossed thereon that indicate one or more borders of respective said keys.