To measure blinds, measure between the jambs of the window to determine the width and from the top jamb to the sill to determine length. To measure curtains, measure between the window casings to determine the width and from the top casing to the sill to determine length. Add inches to the curtain measurements depending on the curtain fullness and length desired. Use a measuring tape for taking the measurements.
When measuring between the jambs for blinds, measure between the inner edges of the jambs on either sides of the window. Blinds are attached to the jamb instead of the casing as this offers greater privacy. Round the measurement to the lower whole number.
When measuring the blind length, measure from the jamb's top to the window sill's top. The blind should be of a length that rests on the sill.
When measuring between window casings for curtains, measure from the outer edges of the casings on either side of the window. For a fuller curtain, multiply the measurement by a factor of two or three.
To determine the curtain length, measure from the casing's top edge to the sill's bottom side. Increase this measurement by two inches to allow the curtain to fall below the sill. If the curtain is to drop till the floor, measure from the casing's top edge to the floor.