How to Measure Windows for Blinds?

This measurement guide shows how to measure windows for blinds. Measuring blinds for either outside or inside mount should not be a complicated process.

How To Measure Windows For Blinds

Whether you already have off-the-rack blinds or you intend to send a measurement to the factory, taking the right measurement will immensely contribute to the final look of your blinds installation.

Measuring windows for blinds should not be a complicated procedure, rather should be fun, easy, and worth trying. Read on to learn how to measure windows for blinds.

How to Measure Windows for Blinds?

First, determine if you want to mount the blind on the inside or outside of the window frame. This will be determined by a couple of factors like the size of your window size, the deepness of the window frame as well as corners of your window.

But do not worry as this measurement guide will cover the most important basics that will help you make the right measurement. And this is the first step to an impressive blind installation.

Inside Blind Measurement:

First, see if your window frame is deep enough. To do this, use a metal tape measure to measure from the wall to the glass (taking into consideration any handles or locks). 2-inch measurement is typically enough for an inside blind. Less than this, go for the outside blind.

Next, ensure the corners of your windows square perfectly. This will ensure the blinds hang correctly.

To check for this, measure the window diagonally in both directions. If the difference isn’t over1/2 an inch, then you are good to go.

Furthermore, measure the width of your window to the nearest 1/8 of an inch. Measure at the top, center, and bottom. Then use the narrowest measurement as your ordering width.

Finally, measure the height at the left, center, and right of the window to the nearest 1/8 of an inch. Use the longest measurement as your measuring height.

An inside mount provides a finished, clean, built-in look without covering any molding, and can give added insulation and privacy.

Outside Blind Measurement:

Start by determining where you want your window covering to be. Then measure the width of the window, adding at least 1 and 1/2 inches to the right and left sides. This helps reduce the outside light.

For height measurement, measure from above the window headrail (anywhere you desire) to the window sill. Measure where you want the window covering to end if you don’t have a window sill.

Make sure to add 1.5 to 3 inches of overlap to the top and bottom. But add overlap only to the top if you want the blinds to rest on the window sill.

An outside mount can make your window appear bigger, wider, and have a longer look. It is also perfect if your window is noticeably off the square.

Nevertheless, you can also use it to hide a not-so-attractive window that you wish to hide.


Noted earlier, measuring your window is the first step to achieving a perfect window blind installation. After that, you can send the measurement to the factory or manufacturing company.

This measurement guide will also be useful when you want to customize off-the-rack blinds that are too long.

Do you find this piece useful? Kindly let me know in the comment section below.

Raymond Williams is a technology writer that lived with computers all his life. He is an expert character that writes articles about Windows, Gaming, Android, and How To Fixes.