Certainly the best fit needs time to carefully measure your window and follow our simple curtains measuring Guide. We recommend using a metal tape measure for accuracy. Curtain measuring Guide If your children's curtains were installed with a simple plastic track, and then follow the steps below: From the top of the track to the desired finished length measurement Measure the length of track, track can extend beyond the window instead of window on each side, to allow the curtains to be back soon to be pulled If your children's curtains were hung in a traditional bar, measuring from the bottom of the curtain rings, to the desired finished length, then measure does not include the length of the head.