What age do they stop growing?
But would like to have some idea on how tall they will be.
Also an approximate on their estimated weight at fully grown.
Well...I have 4 rotties, all have unknown backgrounds.
Ben is 3 yrs old, I adopted him at 10 months old, at a weight of aout 75 lbs. he's 3 yrs old and weight is 82 lbs and he is about 22 inches tall at the top of his shoulder blades (the withers on a horse). He's about 10-11 inches wide at the widest part of his chest (my midget rottie!). That's as big as he'll get - he stopped growing at about 2 yrs old I think.
Baker is about 5 yrs old, adopted at about 3 yrs old. he weighs in at a whopping 125 lbs (should be at about 115, we're working on it!), and he stand about 26-27 inches tall, and is about 14 inches wide at the chest.
Cheyanne is about 6-7, weight is 96, about 24 inches tall, probably 12 inches width at the chest.
Thelda is the 'fat old broad'. About 7-8 yrs old, about 130 lbs (and REALLY fat - on a diet but not working, having thyroid tested this week), she should be about 95-100. About the same height as Ben but much wider at the chest - big boned girl...probably about 13-14 inches wide.
According to the AKC website, a rottie when fully grown should be half as wide as it is tall (24 inches tall should be 12 inches wide) but it varies in all dogs.
I was told they stop growing UP and then the grow OUT...so height comes before width...and that takes about a full 2-3 yrs...
Mentally, some NEVER grow up!
At 18 months, you've got yourself a typical rottie teenager..genetics plays a big role in what they'll grow up to look like, so if you have chance to see the parents, you'll be able to get a better idea of what your dog will look like.
I guess what I'm trying to say is tehre really is not cut and dried answer to your question :D . But hope this helped a bit!
Generally, girls grow in height til 18 months and boys until 24 months (but both grow slowly after 12 months)
Body and head width can take until 5 years old to finish depending upon lines. Mine take 4-5 years to be done and fully physically mature
Diane-Dogs of Frontier
Annie RE,CGC,Wildlife Recovery
Gone-VP Darla SAS 12/00-2/02 U-CD Bea CD,RE,TD,CGC,TT Osteo 3/03 - 2/08 Bonnie CGC AIHA 2/08-8/10, Bill HICs,TT 10/98-8/13