How to Measure

• Use a metal tape measure. Plastic can stretch and give false readings.
• Measure the window in three places and use the narrowest of the three measurements. For width, measure across the top, the bottom, and the vertical center. For height, measure along the right, the left, and the horizontal center.
• Record measurements in inches, rounding down to the nearest 1/8 of an inch.
• Measure all windows, even if they seem to be the same size.

1. Measure the width of the window (inside the trim) along the top, bottom, and vertical center. Make sure to measure inside the trim. Record the narrowest measurement, rounding down to the nearest 1/8 inch.
    
2. Measure the height of the window (inside the trim) along the left side, right side, and horizontal center. Make sure to measure inside the trim at the top of the window to either the top of the windowsill or the length you want the blind to hang. Record the smallest measurement, rounding down to the nearest 1/8 inch.
    
3.  Measure the depth of the window. DO NOT include trim, cranks, tracks, or other hardware. Measure only the space available for mounting brackets, and record your measurement.

1.  Measure the width from the outer edge of the window frame to the opposite outer edge. Measure in three places: along the top, along the bottom, and across the vertical center. Round the narrowest measurement down to the nearest 1/8 of an inch and record it.
    
2. Measure the height from the top outer edge of the window frame to the top of the window sill. Measure in three places: along the left side, along the right side, and along the horizontal center. Round the smallest measurement down to the nearest 1/8 of an inch and record it.

1.  Repeat the measurements above.
    
2.  Decide how far beyond the window frame you want the blinds to hang. Design experts generally recommend adding 1 to 3 inches to the width and 2 to 3 inches to the height for maximum privacy. Add this to your original measurements.