How tall is your dog? (A weird Monday poll)

I'm thick in the "getting to know you" period with Ada and I have just discovered that she is 18.5 inches (47 cm) at the withers. 
 
It is often hard to tell from pics how big your dogs are and I will probably never meet them in person. So, if you feel in the mood for quantification weirdness, grab a tape measure and join in. 
 
How tall is your dog at the withers (shoulders)?  

(She's also 13 kg/28 lbs for the full stats. )