How to Measure Windows for Blinds & Shades

Before Measuring, Choose Between Inside & Outside Mount

Inside Mount

An integrated, clean look and our most popular choice. The window frame needs to meet the minimum depth requirements for your window treatment. A common mistake is overlooking the depth needed for Inside Mount, which can affect the final installation. If you’re unsure about depth requirements, check our blog for more details.

Outside Mount

Outside mount makes windows appear larger and provides better light control. Choose this option if the window frame doesn’t have enough depth for an Inside Mount.

How to Measure Inside Mount Blinds & Shades

Step 1: Measure Width

Measure horizontally inside the window frame in three places: top, middle, and bottom, to the nearest 1/8 inch. Record the smallest measurement as your width.

Step 2: Measure Height

Measure vertically inside the window frame in three places: left, middle, and right, to the nearest 1/8 inch. Record the largest measurement as your height.

Step 3: Measure Depth

Measure the depth at the top of the inside window frame to the nearest 1/8 inch, making sure to account for any obstacles. Record the smallest measurement as your depth.

How to Measure Outside Mount Blinds & Shades

Step 1: Measure Width

Measure horizontally between the outermost points where you want to place the curtains to the nearest 1/8". For optimal light control, it is recommended to overlap each side of the window frame by at least another 3/4".

Step 2: Measure Height

Measure vertically to the nearest 1/8 inch from the top of where you want to mount the curtain (head rail location) to the top of the windowsill, or to the point at which you want the length if there is no windowsill.

Measurement Tips

• 1.Do not deduct the amount from your measurements.


• 2.For interior installations, we will make adjustments to ensure a perfect fit.


• 3.For exterior installations outside the window trim, you may need to extend brackets or spacers to account for trim thickness.


• 4.Measure each window – even ones that appear identical.


• 5.All measurements should be taken to the nearest 1/8 inch.


• 6.Use a metal measuring tape, as cloth measuring tapes may stretch.