Tech Tip: The Ultimate Guide on How to Measure Windows for Blinds or Shades

When it comes to getting the perfect fit for your window treatments, knowing how to measure window blinds the right way is key. Whether you're installing roller shades, Roman blinds, or cellular shades, taking accurate window measurements ensures a polished, custom look that fits like a glove. In this expert DIY guide from Select Blinds, we walk you through how to measure for blinds step-by-step—whether it's inside mount or outside mount, single window or bay. If you’ve ever searched how do you measure windows for blinds or how to measure a window for blinds, you’re in the right place.

We'll show you:

  • How to measure for window blinds with easy-to-follow diagrams.
  • The difference between measuring blinds for windows versus measuring blinds for window frames.
  • What tools you’ll need and common mistakes to avoid
  • Expert tips on how to measure for shades like a pro

Whether you're updating a single room or transforming your entire home, measuring blinds for windows doesn’t have to be complicated. As a trusted DIY brand, Select Blinds handcrafts every product with precision and care. With over 170 customizable products and more than 1,800 colors, you're sure to find the perfect match for your style and space. And the best part? We ship everything free, right to your doorstep.

How to Measure for Inside Mount Blinds or Shades

Inside mount window coverings are installed inside the window frame or casing. They provide a sleek, built-in look that showcases the window's natural architecture.

What You'll Need:

  • Steel measuring tape (not cloth)
  • Pencil and notepad
  • A step stool or ladder for higher windows

Step-by-Step Instructions:

  • Measure Width (Three Places):
    • Measure the inside width of your window frame at the top, middle, and bottom.
    • Record the narrowest measurement to ensure a proper fit.
    • Do not make deductions—Select Blinds will adjust for proper clearance.
  • Measure Height (Three Places):
    • Measure the height from the top inside edge of the frame to the bottom sill at the left, center, and right.
    • Record the longest measurement.
    • If there is no sill, measure to where you want the shade to drop.
  • Measure Depth:
    • Measure the window depth to ensure the product can be fully recessed.
    • Depth requirements vary by product—refer to product specifications on SelectBlinds.com.

Pro-Tip:

If your windows are slightly out of square, inside mounts will still work as long as there are no major variances.

How to Measure for Outside Mount Blinds or Shades

Outside mount window coverings are installed on the wall above the window or on the window trim. They create the illusion of larger windows and offer maximum light coverage and privacy.

What You'll Need:

  • Steel measuring tape
  • Pencil and notepad
  • A ladder or stool (if needed)

Step-by-Step Instructions:

  • Measure Width:
    • Measure the exact width you want the blind or shade to cover. .
    • Add at least 2 to 3 inches on each side (4 to 6 inches total) to minimize light gaps and ensure full coverage.
  • Measure Height:
    • Start from the top of where you'll mount (usually above the trim) to the bottom of the area you want to cover.
    • For blinds that rest on a sill, measure to the sill.
    • For shades that extend past the sill, add 1–2 inches beyond.
  • Mark the Mounting Area:
    • Ensure there’s enough flat surface for brackets to mount.
    • Check for obstructions like molding or handles.

Pro-Tip:

Outside mounts are great for shallow windows or when you want to make windows appear larger and taller.

Want more tips on measuring, decorating, and choosing the perfect window treatments? Visit our design and inspiration blog at: https://blog.selectblinds.com/