How to measure your window for blinds (without holding your breath)

Let's be honest: nobody is afraid of choosing a colour. Everybody is afraid of the tape measure. You hold it against the frame, look at the number, and wonder whether that number will become a beautiful blind or a story you tell at dinner with a slightly forced smile.

Breathe. We have exactly one rule, designed so you never need maths: you give us the finished size. Whatever you want the blind to measure, that is what you type into the configurator. We don't secretly deduct anything, you don't add "a finger for safety". What you type is what you get, to the millimetre.

Three things before you start

One: use a metal tape measure, not the tailor's tape inherited from your grandmother - fabric stretches and lies by a few millimetres exactly when it shouldn't. Two: measure in millimetres, because that is how the blind is made. Three: measure three times. Width at the top, in the middle and at the bottom; height on the left, in the middle and on the right. Windows look straight. They rarely are.

Where you mount decides what you measure

In the window recess, take the opening and use the smallest of the three widths - the blind sits inside the recess and shouldn't rub against the walls. On the frame, measure exactly what you want covered; the blind sits on the window and moves with it, which is a blessing on windows you open ten times a day. On the wall or ceiling, measure the opening and add however much you want the blind to overlap on each side, so the sun doesn't sneak past. And for PVC windows there is the no-drill option with clamps: measure the sash and you're done.

And if it still comes out wrong?

It happens. Even to people who have been measuring for twenty years. That is what the measurement guarantee is for: we remake the blind once, at 30% off, within 30 days of delivery. The tape measure stays a tool, not a test of character.

The guide with diagrams for every mounting type is on the measuring page, and once you have your numbers, the configurator shows you the price on the spot.