Measurement guide

How to measure for window blinds

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A person holding a tape measure across the top of a window

2 min: per window
1: tool needed
3: steps
0: deductions

Tools you need

Nothing special. If you have these three, you're ready.

Metal tape measureNot cloth - cloth stretches. Metal is accurate to 1/8".

Pen + paperWrite as Width x Height. Example: 34 1/4" x 64".

PhoneTake a photo of the window. Helpful if you call us.

Inside vs outside mount

Pick one before you measure. Everything below follows from this.

Same tape, different numbers

Blind mounted inside the window frame, with the trim visible around it

Inside mount

Recommended

Clean, built-in look

Needs 2" depth inside the frame to mount flush - 3/4" minimum to mount at all
Small light gap is normal, about 1/4" total. Factory deducts for smooth operation
Shows your trim. Most popular in Canada

Best for: Living rooms, kitchens, any window with a deep enough frame

Blind mounted outside the window frame, overlapping the trim

Outside mount

Bigger look, blackout

Covers the trim

Covers trim. Makes the window look larger
No side gaps. Best for max blackout and privacy
Mounts on wall or trim above the window. No depth needed

Best for: Shallow frames, blackout bedrooms, patio doors, covering trim you don’t love

3 steps, start to finish

Choose your mount, then measure width, then height.

2 min / window

Choose inside or outside
This is the only decision. Everything else is just numbers.
Is your window frame 2" deep or more?
Yes
Inside mount
Clean, built-in look. Most Canadians choose this.
No
Outside mount
You don’t have the depth. Outside works on any window.
Want max blackout? Choose outside mount even if you have the depth - zero light gaps.
Quick check: stick your finger in the frame. If your knuckle disappears (about 2"), you have the depth.
02
Measure width
Same tape, different spot depending on your mount.
Inside mount width
Measure inside the frame at the top, middle, and bottom
Circle the smallest number - that’s it
Don’t deduct. The factory deducts 1/4" automatically
Order widthsmallest measurement
+1"-2"+1"-2"
Outside mount width
Measure the width you want to cover
Add 2" to 4" total - 1" to 2" each side
That total is your ordering width
Order widthcoverage + 2" to 4"
03
Measure height
Left, middle, right - same idea, turned sideways.
Inside mount height
Measure left, middle, and right inside the frame
Use the longest number
That’s your ordering height
Order heightlongest measurement
+3"-4" above
Outside mount height
Measure the height you want to cover
Add 3" to 4" above for mounting
That total is your ordering height
Order heightcoverage + 3" to 4"

Record as Width x Height. Example: 34 1/4" W x 64" H - width first, always.

Zebra shades - read this: Fabric will be 7/8" narrower than ordered width due to mechanism & brackets. This is normal. Light gap on sides is by design for smooth operation. If you need edge-to-edge blackout, order Outside mount + 4" wider.

Pro tips

Measure every window, even if they look the same. Houses settle - 1/4" variance is common.
Metal tape only. Don’t use cloth, a ruler, or a phone app. Steel tape, 1/8" precision.
Measure twice. Once fast, once slow. If they match, you’re good.
Write Width x Height, not Height x Width. The factory reads the first number as width.
Don’t overthink deductions. Order the exact frame size for inside mount - we deduct 1/4" for you.

Common mistakes to avoid

Deducting yourself - We already deduct 1/4" for inside mount. Deduct too and it’ll be too small.
Measuring trim to trim - Inside means inside the frame, not the outside trim. Feel for the inside edge.
Using one window for all - Every opening is slightly different. Two extra minutes saves a return.
Rounding down - Order to the nearest 1/8" - not 1/2", not the nearest inch. Precision matters.
Forgetting depth - Less than 3/4"? Inside won’t mount. Switch to outside.

Safety: Use a stable step stool. Don’t lean out windows. Metal tape can snap back - keep your face clear when extending it. Keep kids and pets clear while measuring. If a window is high or awkward, call us and we’ll guide you live.

Quick order checklist

Width___ ___⁄16"

Height___ ___⁄16"

Mount[ ] Inside [ ] Outside

Example: 35 3/8" x 64" - Inside

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How to Install Window Blinds

Measured right? Install takes 15 minutes per window. Same Canadian DIY style, no drill drama.

View install guide