You asked the magic question, let's see how many answers I can give you. Depending on the fabric line, company, and if it is an official jelly roll--40. But a shop may cut their own, colors may be duplicated if the line has fewer prints or if the price is real cheap. Look at your pattern, most will say use all of the jelly roll, pick out x color and y color or maybe use 2 () or more jelly rolls. If I am buying I watch for the number 40 and also look at the color legend to see how many prints there are. Some people look at the edge, pinked or smooth, so if you cut your own, watch the size as 2 1/2 in is norm.
Kathy in Colo