Consider some basic geometry when measuring sleeve length.

I always measure sleeves from the underarm to the wrist. Plus I recommend you measure something you wear to determine your sleeve length for your knitting.

Consider this:

A shaped sleeve is shaped with an angle. The measurement of the "A" line in this drawing (15.3") is longer than the "B" line (14.6"). It's just geometry.

If you measure the sleeve seam of your sweater and use that measurement, you sleeves will be longer than you expect.

Lessons learned:

• Measure straight down and don't follow the angle
• Account for any hem, ribbing or cuff you may be planning