How to Measure for Blinds
Make sure you get the perfect fit!
When sizing blinds for your home’s windows, it’s important to be precise so your blinds don’t end up too wide or too narrow. Read on for information about the different mounting styles of blinds and drapes and a step-by-step guide on how to measure for blinds.
Mounting Types
How to Measure Windows for Blinds
Mounting Types
There are two ways to hang your blinds and shades: inside mount and outside mount, illustrated below. Choosing one of the two mounting styles is the first step in understanding how to measure windows for blinds. Read on to learn about how to size blinds for each.
Inside mounted blinds and shades are mounted within the window frame or casing, which means that the blinds are narrower than the window frame. This mounting style is clean looking and doesn’t protrude into the room at all.
Outside mounted blinds and shades overlap the window frame and hang from an upper headrail. This style of mounting protrudes a bit and often makes the window appear larger.
Tip!
For both inside and outside mounting, the window needs to be set at least 1” deep in the sill. If the window isn't deep enough, the blind or shade will either protrude too far or rub up against the glass.
How to Measure Windows for Blinds
How to Measure Windows for Inside Mounted Blinds
Step 1: Measure the width of the window frame.
Measure from inside edge to inside edge at the bottom, middle, and top of the window. Record the narrowest measurement.
Step 2: Measure the height of the window frame.
Measure from the inner edge of the upper frame to the top of the sill (or however far down you’d like your blinds to go) along the left, middle, and right side of the window. Record the smallest measurement.
Step 3: Deduct 1/4" to 1/2" from the width measurement to prevent your blinds from scratching the sides of the window frame.
Step 4: Deduct 1/4" from the height measurement if you don’t want your blinds to rest on the sill.
How to Measure Windows for Outside Mounted Blinds
Step 1: Measure the width of the window including the molding or frame.
Step 2: Measure the height of the window including the molding or frame.
Round your measurements up, because you can easily adjust the length of longer shades or blinds.
Step 3: Add at least 3" to the width measurement for an overlap of 1 1/2" on either side of the window frame.
Step 4: Add at least 3" to the height measurement.
Headrails typically add about 2" to the height of your window frame and you always want to round up for height, as blind height is easy to adjust.
Step 5: For vertical blinds, add 4” to the width and 3” to the height.
Overestimating the width measurement will help compensate for when the vanes or slats are fully opened.
