Split plus on numpad


I was wondering what is the usual reason for splitting the + key on the numpad and how would you normally map a numpad like that? Is there some kind of a “conventional” mapping (maybe an OEM board which has a layout like this?) or do people just use whatever ?

The reason I’m asking is I’m about to build a KBD19x, and I think I might want to build it with a split +, but I’m not 100% sure … If I do decide to go for it, I’d probably put + and - in place of the 2u +, remove the useless numlock from the toprow and use the two freed up keys for PrtScr and Pause/Break

What do you think? Do you have a different layout suggestion?



Would the plan (in removing the num lock key) be to trigger the alternate functions (Home, End, Page Up, Page Down, Insert, Delete, and the arrows) based on a modifier key, or to remove them entirely?

Broadly, I think I’d rather keep the / and * where they are and use the freed-up space from shifting the - to have an = key (to make it more useful for writing algorithms) but I’m not sure how well-supported that would be by various keysets.


The KBD19x has dedicated arrow keys, as well as a four key nav cluster above the numpad which I would map to Home/End/PgUp/PgDn … Delete is to the right of F12 and I almost never use Insert, so I don’t need any of these repeated on the numpad, making Num Lock useless.

I don’t remember seeing a numpad “=” in any of the keysets I’ve been looking at recently. Another variant would be to put brackets there like the Amiga keyboards used to have (would be very useful for programming) but finding keycaps for that is probably an even taller ask than a “=”:


That makes sense! Probably would be equally hard/useful to have parens there. I suppose the enter key generally covers most calculator-style use cases for an = key in the numpad cluster, but I’d still love to just have a little pad completely focused on writing out mathematics.


The usual reason is to cater to the original G80-1800 layout (which inspired the ‘truncated 1800’ layout you see in the likes of KBD19x and TX-CP etc etc). All OG 1800 boards come with a split numpad plus key to make room for the relocated Nav cluster


truncated 1800

You mean Lil’ Shorty 1800? /s


That makes sense, thanks.



I split the plus on my TXCP numpad to gain an extra key so that I can have pgdn physically below pgup.

I also have numlock on a layer (where delete is) so that I don’t accidentally ever turn it off, which in a way gains an extra dedicated key


Putting numlock on a layer is a neat idea, I think I’m gonna use that. Thanks for sharing! :slight_smile: