what is the earliest a egg will start to tap/peep/pip?

[missychicky]

I think My egg is tapping but it seems to early for it to be doing so. What is the earliest an egg will start to tap/peep/pip?

 

[PunkinPeep]

I don't know what the earliest possibility is, but i regularly have hatches on day 19 with tapping starting 24-ish hours before.

 

[Kedreeva]

I just took a duck egg off the incubator for lockdown and it'd pipped on the day equivalent to day 18 in chickens. Have heard of chickens pipping on the 18th as well.