How to Measure Window Blinds

Why Measuring Your Window Blinds Matters

Getting the right measurement is the most important step before ordering new blinds. A perfect fit ensures your blinds look sleek, function smoothly, and provide full light control and privacy. Whether you’re upgrading your living room or installing new shades in your office, this simple guide will show you how to measure window blinds accurately—even if you’ve never done it before.

1. What You’ll Need

Before you start, grab a few basic tools:

• Steel measuring tape (for accuracy)
• Pencil and notepad (to record measurements)
• Step ladder (for tall windows)

Tip: Always measure in inches and to the nearest 1/8″ for the most precise fit.

2. Decide on the Mount Type: Inside or Outside

There are two main mounting styles for blinds, and how you measure depends on which one you choose.

Inside Mount (Fitted Inside the Window Frame)

Inside mounts create a clean, built-in look and are perfect if your window has enough depth.

• Width: Measure across the top, middle, and bottom of the window opening. Record the narrowest measurement.
• Height: Measure from the top inside edge to the bottom sill on the left, middle, and right sides. Record the longest measurement.
• Depth: Check that your window frame is deep enough for the blind type you want (refer to product specs).

Order blinds using the narrowest width and longest height.

Outside Mount (Mounted Over the Window Frame)

Outside mounts are ideal if you want to cover trim, block more light, or if your windows have a shallow frame.

• Width: Measure the exact area you want to cover. Add 2–3 inches on each side to prevent light gaps.
• Height: Measure from where you’ll install the top of the headrail to the desired bottom point. Add 2 inches for better light control and coverage.

Order blinds using your exact desired width and height.

3. Double-Check Your Measurements

Once you’ve taken all measurements:

• Write them clearly in the format Width × Height (W × H).
• Measure twice to confirm accuracy.
• Label each window (e.g., “Kitchen Left” or “Bedroom 2”) to avoid confusion when ordering.

Mistakes often happen when measurements are flipped or rounded—so take your time!

4. Common Measuring Mistakes to Avoid

• Guessing or rounding numbers — always measure precisely.
• Using a cloth tape measure — steel tapes give more accurate results.
• Forgetting window depth — some blinds require a minimum depth for inside mounts.
• Measuring trim instead of the opening — for inside mounts, only measure the inside frame.

5. Helpful Tips from LazBlinds Experts

• For bay or corner windows, measure each section separately.
• If you plan to install multiple blinds on one large window, leave at least ½ inch between each for clearance.
• For vertical blinds, measure the height from the top of the mount to about ½ inch above the floor.
• Always check the product specifications for mounting requirements before ordering.

6. What to Do After Measuring

Once your measurements are ready, you can:

• Browse LazBlinds Style Inspiration for tips on choosing the right style and material.
• Explore our Measuring & Installation Services (if available) for professional support.
• Keep your notes handy—you’ll need them when customizing your order online.

Learning how to measure window blinds properly ensures you get a flawless fit every time. With the right measurements, your blinds will look custom-made, operate smoothly, and elevate your home’s design.

For more expert window treatment tips, check out our full LazBlinds Installation Guide — your go-to source for measuring, cleaning, and styling blinds with confidence.