Board Thread:Theories and Rumors/@comment-30938718-20180803102949/@comment-36858256-20180910020237

I think

Iron Baron: 40 - 60 years old

Garmadon: 140 something (it is said in the movie and i know they are not canon to eachother)

Harumi: Dead but i think she died as a 16 year old or 17.

Time Twins: 60 - 70 years old

Nadakhan: 100 - 400 years old

Morro: Dead but i think he died as a 20 - 30 year old.

Chen: Dead but i think he died as a 60 - 70 year old, born around the time the time twins were born

Overlord: 700 - 3,000 (Around the time FSM created ninjago)

Pythor: 40 - 80 years old

Samukai: Dead but i think he died as a (i noticed that skeletons are dead human bodies) so 90 - 140.