Domain age, as the name states, is determined by the age of your domain, being an Australian blogger with an Australian domain, this usually works to my advantage. I say this because Austrailan domains, unlike other TLDs, have a minimum registration time of two years hence locking in my minimum domain age at two years instead of one. Australian domain names also have a barrier for entry as there are restrictions on who can own one and for what reason it can be owned for, this gives Australian domain slightly more trusts than cheaper generic TLDs.
As this is a factor which is largely out of our control, I suggest that you don’t think about it too much. Domain age will come over time and you probably won’t even know what hit you when it does. I have seen a noticable jump in rankings after my older domain (Pixel Square Production) passed the two year age mark. I had implemented no SEO changes nor have I been actively adding links, so Google basically just decided that after two years, my domain was trusted more.
However, if you are really concerned with domain age, then I would recommend you look into purchasing expired / expiring domains, or buying an old domain name off digital point or namepros.Â You will notice that there are a lot of people selling domains, however you will need to carefully weed through all of them to find one with a name which would fit your purpose as well as demographics.
Note that you shouldn’t look at the page rank of the domain when purchasing. I say this as there are shady sellers who artificially inflate the domain’s page rank by adding a large amount of inbound links to them, however as soon as they sell the domain, those inbound links would disappear and the domain will lose its page rank.Â Only purchase a domain according to its merits, such as domain age, TLD, name as well as if it fits your purpose. You may also want to run a quick background check on the domain Via Google to see if there are any undesirable mentions linked to it.