If you're a singer who doesn't play an instrument, of course you may have no idea what key you're in, or what might be a do-able key for others. No surprise there.

The only way to find out is to sit down (at some other time than the singaround) with a player or a pitch pipe and search around until you identify what key is comfortable for you and/or others. (What's best for you may be something like E-flat -- not so handy for others, but a compromise to D might work.)

If you do this for some of your favorite songs, then you can remember (or carry a note as to) what keys they are and let the instrumentalists know, if you really want them to join you. And, if you do this for several songs, you might be able to guess at a key to try for other songs, if they mostly end up in the same area.

But, don't be shy about singing unaccompanied - it's a fine and under-appreciated thing.

If you want people to sing along, that's great, but if your voice is pitched in a hard place for them, they'll just have to find a harmony. Not much you can do about it.

~ Becky in Tucson