Key of voice

This may be a strange question but is there a way to tell what key a person’s voice is in when they sing?

Hi jmshimkoo1 try the key finder app, not perfect but it gets it right 80% of the time, others may be better alternatively a decent pitch pipe like a Hohner true tone and listen for a match, that’s what I use but don’t forget to tell the singer what you’re finding, a lot won’t know their key. Jay1

Thanks Jay1