I have a nursing home that uses keypads for access/departure control they don't need the security of a 4 digit code and would like something easier to use. Are there 2 or 3 digit keypads? I have suggested RF or magnetic but I'm not sure what to use there either.

I have never seen a two or three digit keypad. If they are not concerned about security how about just useing a RTE push button? For ease of use a magnetic reader is the way to go. Corby makes some basic units they may fit your needs.

HID makes a stand alone single door controller called an 'Entryprox'. all the programming is done thru a keypad on the unit and uses any standard HID card

One of my customers has a 3 digit (2 numbers and the * key) in use.
I'll try to get by there and get a manufacturers name and the model number for you.

I haven't forgotten you Merritt. I had to cover a lot of miles yesterday and today and have not been able to get by there. I have another out of town job in the morning but maybe I can get there tomorrow afternoon.

Well, how about makeing the first two digits the same; 2254, 3342

I went by today and there are no markings what-so-ever that indicate a brand name on the outside of the keypad and the customer really wasn't comfortable with me taking it off the wall to get the information.
Sorry I couldn't help.

ISTM that either IEI or Corby stand alone keypads can be programmed for short codes with a bit of effort. Both vendors have full install manuals on line for their conventional keypads... and excellent phone support (hint, hint), number on website.

When you say keypad I think of something controlling a door strike or mag lock. And there are plenty of suggestion above. But if you are looking for a mechanical lock here is a suggestion:

https://www.codelocks.co.uk/push-button-lock.htm

You can use one digit if you want. If they need a keypad on both sides this is the only company that I have found that makes one that is ADA compliant lock i.e. handles on both sides.