How To Measure a Window for Blinds

The Blind guy • June 29, 2026

Getting the right fit for your window blinds starts with one simple task: accurate measurements. It sounds easy enough. But even a small mistake may lead to gaps in coverage, poor light control, and more. If you’re planning to order custom window treatments, knowing how to measure a window for blinds is the first step toward a look that works well.

A happy woman using a tape measure to measure her window for new custom blinds

Our team at The Blind Guy Coeur d'Alene is here to share some steps to help you measure a window for blinds with confidence.

Start With the Right Tools

Before you start, you’ll need to gather the right tools for measuring blinds, such as:

  • Tape measure.
  • Pencil.
  • Notepad.
  • Step ladder.

Decide Between Inside-Mount or Outside-Mount Blinds

Deciding between an inside-mount and an outside-mount blind will determine how you take your window measurements.

For example, blinds with an inside mount sit inside the window frame. It looks clean and built-in. However, your window must be deep enough to accommodate the blind.

An outside mount, conversely, installs above and possibly beyond the window frame. This option works well if your window is shallow or slightly uneven. It can also make a window appear larger.

How to Measure for Inside-Mount Blinds

Accuracy matters most when measuring a window for inside-mount blinds, since you’re working within a fixed space.

Here are a few steps for measuring inside-mount blinds:

  1. Measure the width at the top, middle, as well as the bottom of your window opening. Use the narrowest width, as this helps ensure the blinds will fit without scratching the frame’s interior.
  2. Measure the height on the left, center, and right sides, and use the longest height to help guarantee full vertical coverage.
  3. Measure the depth of the frame to figure out if your chosen blinds will fit inside the frame.

As a good-to-know, even if your window looks square, it might not be. Homes settle over time, and small variations are common, so it’s important to measure your window each time you install a new window treatment rather than using older measurements just in case.

How to Measure for Outside-Mount Blinds

Outside-mount blinds give you more flexibility, but you still want as much precision as possible in your measurements.

To measure for outside-mount blinds, here are some steps:

  1. Determine the complete area around the window that you need to cover. You can improve light control and privacy by adding 1.5 to 3 inches to your horizontal measurements on either side.
  2. Establish the height of the headrail and the bottom location where the blinds should end.
  3. Add additional height to cover the entire window trim, if desired.

What Are Common Mistakes to Avoid When Measuring for Blinds?

Even careful, experienced homeowners can make measurement mistakes. Even a small oversight can delay your project or lead to costly adjustments later.

Watch for these common issues:

  • Measuring only once instead of double-checking.
  • Using the wrong mount style measurements.
  • Forgetting to account for obstructions like handles or cranks.
  • Rounding numbers instead of recording exact measurements.

Get Professional Blind Measurements Near Coeur d'Alene, ID

When you want a precise fit and a guaranteed smooth process, working with a professional team makes a noticeable difference. Measuring mishaps is where most ordering mistakes happen. That’s why many homeowners look for professional blind measurements near Coeur d'Alene, ID, with our team at The Blind Guy.

Skip the guesswork when it comes to measuring for window blinds, and contact us online or call (208) 667-6908 to schedule a free consultation with our team.

The Blind Guy Coeur d'Alene proudly serves Priest Lake, Bonners Ferry, Sandpoint, Athol, Rathdrum, Hayden, Post Falls, Coeur d'Alene, Wallace, St. Maries, and Harrison, ID.

Man preparing his backyard bright red awning for the spring and summertime on a nice day
By The Blind guy May 26, 2026
Learn how to get your awning ready for spring and summertime with our best tips. Contact us about awnings for backyards near Coeur d'Alene, ID!
Living room with a modern rustic interior design and wood window blinds to enhance the space
By The Blind guy April 20, 2026
Discover modern rustic window treatments that blend natural warmth with clean design. Contact The Blind Guy Coeur d’Alene in North Idaho to learn more!
Child's playroom with cordless shades at the window and a play kitchen at the room's center
By The Blind guy March 12, 2026
Learn how to design the perfect kids’ playroom with cordless shades or motorized blinds. Contact us for kid-safe window treatments near Coeur d'Alene, ID!
Chic and sleek custom Roman shades on a large window in a luxurious bathroom
By The Blind Guy February 20, 2026
Enhance your home with custom Roman shades for style and privacy. Shop Hunter Douglas Roman shades near Coeur d'Alene, ID, with The Blind Guy Coeur d'Alene!
Hunter Douglas cellular shades on expansive windows overlooking a view with mountains in the distanc
By The Blind Guy January 22, 2026
Learn how you can prioritize your home’s energy efficiency this winter with cellular shades near Coeur d’Alene, ID. Contact the Blind Guy Coeur d’Alene today!
A snowy deck in a residential backyard, overlooking a picturesque nature view with hills and trees
By The Blind Guy - Coeur d'Alene December 16, 2025
Learn how to prepare your retractable awnings for the fall and winter season near Coeur d'Alene, ID. Contact us for more information on caring for awnings!
A lavish living room with custom drapes paired with a sheer layer at the window near Coeur d'Alene,
By The Blind Guy - Coeur d'Alene November 14, 2025
Explore how to add drama and style to your living room with custom drapes near Coeur d'Alene, ID, at The Blind Guy. Contact us for expert advice today!
Chic and practical blinds as kitchen sink window coverings in a sleek, contemporary space near Coeur
By The Blind Guy - Coeur d'Alene October 14, 2025
Explore four reasons why you should upgrade your kitchen blinds this year, including better durability. Contact The Blind Guy Coeur d'Alene today to learn more!
Outdoor shades with dark green and white stripes, covering a residential patio with white wicker fur
By The Blind Guy - Coeur d'Alene September 4, 2025
Refresh your patio with outdoor shades, vertical blinds for sliding doors, and more. Shop outdoor patio shades near Coeur d’Alene, ID, at The Blind Guy!
A retractable awning, opened and covering a home's sliding glass door and the patio near Coeur d'Ale
By The Blind Guy - Coeur d'Alene August 6, 2025
Enhance outdoor living with a SunSetter® or Sunesta® awning from The Blind Guy. Shop retractable awnings near Coeur d'Alene, ID, for comfort and energy savings!