How to measure for roller blinds
Start by choosing how your blind will fit. We’ll show you where to measure and what to enter when ordering.
Measure inside the window recess
Don’t subtract anything yourself.
Illustration only · not to scale
Measure the width at the top
Measure across the inside of the recess where the roller and brackets will sit. Keep the tape straight and level.
Measure the drop
Measure from the top of the recess to the sill at the left, middle and right. Record the smallest drop.
Choose “Recess” when ordering
Enter your width and drop in your chosen unit. Check for handles, tiles and other obstructions before ordering.
Measure the overall size you want
The fabric will be narrower than the overall blind. Plan your coverage with this in mind.
Decide where the blind will sit
Choose the position above the recess and check there is space for the brackets and controls.
Measure your overall width and drop
Measure between your intended outer bracket positions. Measure the drop from the top of the blind to where you want it to finish.
Choose “Exact” when ordering
Enter the finished overall dimensions you want. We won’t make a recess deduction.
Measure for your Twist Fit roller blind
A tension fitting holds your blind inside the recess, without screw holes.
Use the smallest width and drop from the measurements below.
Measure within the recess · illustration not to scale
Measure the width in three places
Measure across the top, middle and bottom of the recess. Record the smallest width.
Measure the drop in three places
Measure from the top of the recess to the sill on the left, in the middle and on the right. Record the smallest drop.
Enter your measurements
Select Twist Fit on your chosen roller blind. Enter the smallest width and drop, checking that the unit matches your measurements.
Subtract your smallest width from your top width. If the difference is more than10mm, Twist Fit is not suitable for that recess. Contact us for help choosing another fitting.
Allow at least 50mm of clear space
Check the space between the front edge of any obstruction, such as a window handle, and the front of your recess. You need at least50mm (5cm)clearance.
Allow for the fabric width
The fabric is36mm narrower than the ordered widthto accommodate the mechanism and controls. This is separate from a fitting allowance.
Side view · check any protruding handles
Blind width ≠ fabric width
The overall width includes the brackets and controls. The fabric sits between them, so it is narrower than the complete blind.
When planning an outside-recess fit, allow enough coverage for the fabric—not just the fittings.
A few helpful answers
Do I need to make any deductions?
For a standard recess order, enter the full recess size. We deduct 3mm from the width and make no deduction from the drop. Don’t subtract this yourself. Exact-size orders are made to the overall dimensions you provide.
What if I have tiles or window handles?
Check for anything that could obstruct the brackets, fabric or bottom bar. If tiles make the opening narrower lower down, contact us with the width at the top and between the tiles before ordering.
Can I measure an existing roller blind?
For an exact-size replacement, measure the complete blind including its fittings, rather than just the fabric. Check the new blind’s fabric coverage too, as fittings can differ.
Which units should I use?
Our product page lets you choose millimetres, centimetres or inches. Make sure the selected unit matches the measurements you enter.
Need a hand with your measurements?
Talk to us before ordering—we’ll help you find the right fit.