1.25 is too low for the US, too. However, we're just establishing the minimum, so I erred on the low end. 1.5 or 2.0 would probably come closer to reality.
It's highly individual. Mine is about 2.25 because of an infuriating rule about deducting health care premiums. bdunn's course Double Your Freelancing Rate[1] has a really good in-depth discussion on how you can figure this out for yourself.
