Found a great pattern but the gauge does not match the yarn gauge? Here's your tip.

If your pattern gauge is 5 sts/Inch and you can cast on 100 stitches that equals 20 inches (100/sts to the inches)

Your yarn choice is 4 sts/inch. Here's the conversion:

100 sts/5sts to the inch = ______ x 4 (sts to the inch) = the number of stitches to cast on. Be sure to check for pattern multiples and design, and adjust accordingly.