How old?

[JPGallagher]

I roughly know the ages of all of my tarantulas, bar one. The others I obtained when they were young. But my G. rosea I acquired when she was an adult and people have, on occasion, asked me her age. I have no idea. Is there any way of ascertaining the age of an adult tarantula?

[Colin D Wilson]

Not really just by looking at it, all tarantulas grow at different rates due to differing temps, humidity, availablity of food etc, once they get to adulthood they pretty well look much the same until they eventually pass on due to old age.
If you assume it had a fairly good upbringing then if it's female she's between 5 and 15 (ish), it should start another conversation (and you can educate people further) when they say "oh i didn't think they lived that long!"