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Your question is a little vague. If you're asking about how much wider the rough framing should be than a pre-hung jamb set, most guys will add a quarter inch to each side for shims, so the answer would be 1/2 inch wider.
Personally, I like to take an extra minute during framing to make the hinge side studs perfectly plumb and square, then I can nail the jamb directly onto the framing. This way I only need the framing a quarter inch wider than the jamb set.
for example, for a 36" door is there a perfered rough opening and so on for a 32" or a 6' french, all prehung.
Gotcha. Some people will say you can just add 2 inches to the door size and you'll be o.k.
Unfortunately, if you order three 36" doors from three different manufacturers, they'll all be a different width when you actually put your tape on them, so beware.
But if you don't have your doors on site when you're framing, you have no choice but to guesstimate.
The phrase "rule of thumb" comes from a British judge in the 1700's that said a man may legally beat his wife, provided that he used a stick no thicker than his thumb.