He's still a kid 
Aren't Ratchet and Jak (from the Jak and Daxter series) around the same age?
I think they are, like it said in Jak X 
(Well, Ratchet's profile says he's 18) and he was in his Deadlocked armour.
Ratchet is 2 Lombax years or approximatley 25 anything else years apparently…
also I think I heard Jak is about 15 in the first Jak and Daxter game…
but I might be wrong
Aren't Ratchet and Jak (from the Jak and Daxter series) around the same age?
According to their profiles in Jak X: Combat Racing, Jak is a year older than Ratchet, even if I think he looks a bit older for his age. At first I thought Jak was around in his early 20's in Jak II until I found out he was actually 17 in the game. 
So therefore, you're right lombaxdude! Jak was 15 years old in Jak and Daxter: The Precursor Legacy. :oui:
Ratchet is 2 Lombax years or approximatley 25 anything else years apparently…
also I think I heard Jak is about 15 in the first Jak and Daxter game…
but I might be wrong
I dont think the Lombax years is canon anymore… (I do remember it from an Insomniac email YEARS ago…
and well, it appears to me that in the series they just use human/earth years when mentioning years and ages. Just to avoid confusion among us
I guess, the only thing that's for sure is that Ratchet is pretty immature but with some serious bits, which would make him somewhere between 17 and 25 in human years. And if we consider the height difference (I know it's a pretty slippery thing to judge upon) between him and Alister then we may think that he must be actually quite young. Like 17-19, not more. And Alister actually treats him as if Ratchet was a teenager. But I can't say that it's for sure.
well this is a surprise.
True, unless Lombaxes continue to grow throughout their lives? Still doesnt explain why Angela is so tall; she's even taller than Azimuth! (I think she grew up on a low gravity planet) well, like with humans, not everyone is the same height… so it could just be that.
And maybe Lombaxes simply grow slower than us
Or Angela might be taller simply because female lombaxes are supposed to be taller than male X)
Considering all these things we'll never know Ratchet's true age unless the guys from Insomniac'll tell us intentionally or not X)
Argh, I wish we could see another female lombax, just so the fans can stop fighting with each other about what they look like and such 
we could of at least seen his mother… (in a picture, like Kaden)
but it would be funny if it turned out to be that females are supposed to be taller XD
but it would be funny if it turned out to be that females are supposed to be taller XD
Agree, that would be hilarious.
On the age thing, I think he's around his early 20's
Ratchet's age in the first game was: 3.1 years old in Lombax years. In human years, this would equal 15.5 so you could say that Ratchet was a 15 year old Ill-tempered teenager. 
Ratchet's age in All for One was: 4.9 years old in Lombax years. In human years, this would equal 24.5 so you could say that Ratchet is a mature, understanding, caring and reliable 24 year old Lombax. 
From the first R&C game upto the most recent game, Ratchet has aged by 10 years! So he's obviously not a teenager anymore. Now that's a big difference!
I take it that I've solved this two year old thread, right?
When you first play ACiT you see a little cutscene where Qwark is having an interview and he explains that ToD takes place 2 years before ACiT.
I don't know day & month when Ratchet was born, but I know he could born in 1987.
Then in the 1st game(when the adventure's begin), he's 15 years old. Today, he's 25!
If you(the youngest fangirl of Ratchet) are reading it, sorry to say it, but it's true. And it can be sad for you, but Ratchet's got a girlfriend(Sahsa P.), already;0!