How to measure for blinds for a window – including roller and Roman blinds

Trying to find out how to measure blinds for windows to guarantee the perfect fit? You've come to the right place. We have the exact measurements you need to take whether you are fitting your blinds outside the window recess, inside the recess and fixed to a wooden window frame.

Thanks to our friends at Loom & Last, who have helped us out with this foolproof guide to measuring blinds for windows, whether you are looking for kitchen blinds or planning how to dress a bay window.

We recommend that you use a metal tape for accuracy. We've also touched on a few little safety tips, to make sure your blinds are safe around small children.

How to measure for Roman blinds

1. Where do you want to hang your blind?

You'll have three options for this. Inside the window recess...

...outside the recess...

...or fixed to the wooden window architrave

2. How to measure inside recess Roman blinds

If your blind is going into a recess, the width measurement is more critical. Measure the width of the recess in at least 3 points– top, centre and bottom.  You need to choose the narrowest width for the width of your blind or it won’t go up and down smoothly.  A lot of windows are not perfectly straight, even in new homes.

For the drop, measure from the top of where you want your blind to be to where you wanted the blind to end when it is fully down.  In a recess, this will be the height of the recess.  Make this measurement as accurate as you can – you want it accurate within ½ cm.

3. How to measure for Roman blinds for outside a recess or into window architrave

If your blind is fitted outside of a recess onto a flat wall, then the width is not so critical because it doesn’t have to ‘fit into’ a space. We would usually say add about 8cm either side of the recess edge.

That’s your width sorted.

For the drop, measure from the top of your blind to where you want to end of your blind to be.  Again, typically we would suggest 8cm or so below the window sill.

4. Do you want the chain on the left or the right?

This is simple but you will need the information at your fingertips to be ready to order.  Do you want the chain on your blind to be on the right or the left?

If it is a single blind and, say, you’re left handed, you would want the chain on the left to make it easy to use. Just make sure it’s easily accessible and doesn’t involve a big stretch or awkward manoeuvring around furniture to get to.

If there are two windows side by side, you might choose to have the right hand blind with a chain on the right, and the left blind with a chain on the left so that they’re out of the way and not central to the blinds’ installation, which might ruin the look of them.

Once you know which side, there are a couple of options with the sidewinder chain or cord and cleat to choose from, it’s very much a personal choice on that.

How to measure for roller blinds

1. Where do you want to hang your blind?

Again, you'll have the option to hang them on in the inside recess, outside recess or fixed to a wooden window frame.

2. Do you want standard or reverse roll blinds?

However another key point to remember is that Roller blinds can work in two ways – standard and reverse roll. This refers to the way in which the fabric comes off the roller.

Standard roll means that the fabric comes off the back of the roll staying as close to the window as possible, but it does mean that the roller is the colour of the roller backing, not the fabric (if you are using a laminated fabric roller blind).

A reverse roll means the fabric comes off the top of the roller but is some distance away from the window, which is not ideal for bedrooms with blackout blinds, for example.

3. How to measure for inside recess roller blinds

Measuring for roller blinds is almost the same as measuring on Roman blinds. However, the recess must be a minimum of 6cm deep otherwise there will not be enough space to fit the blind brackets.

4. How to measure for roller blinds for outside a recess or into window architrave

With the width, Loom & Last recommends at least an 8cm overlap outside the frame, particularly if you have a blackout blind and are concerned about light leakage.

When looking at drop, check for any obstructions that might stop your blind hanging freely.

Child safety information when measuring for blinds

Buy now: Keswick Roman blind, £43 a metre, Loom & Last

Any trustworthy blind manufacturer must know the installation height of a blind so they can make sure the chain or cord is at least 1.5 metres from the floor.

To get this measurement, you simply measure from the floor to the top of your blind.  This is called the ‘installation height’ and you should always be asked for it when you order a blind. If you are not, your blind maker is breaking the law.