That's what we'll focus on here. The length of your curtain and width of your curtain are very important factors in choosing the right curtains for your space. Getting the measurements accurate means you won't have to go through the hassle of returning something that isn't the right length or doesn't fully cover the width of your window.
Measuring the Length
First thing's first: how long do you want the curtain to be? This isn't asking for the exact measurement, rather it's which look you prefer. Do you want the curtain to fall at the sill, just brush the floor, or puddle at the floor?
For the sill length, you want to measure from the curtain rod down to the top of the window sill or just below the apron. This is most typically the choice for kitchen and bathroom windows.
For the floor length, you want to measure from the curtain rod down to the floor, and maybe take a half inch off if you will be hanging with clip rings rather than directly from the rod. The standard size most people need for this is 84 inches. However, if you hang your curtain rod higher, you will need longer curtains. This look is common in most bedrooms, living rooms, and dining rooms.
To get the puddled look, you want to measure the same way you did for the floor length, but you will need to add at least 6 more inches to the length to get that puddled look. For many, 95-inch curtains will do the trick. But again, if the curtain rod is higher, longer curtains will be needed. While this creates a chic and glamorous look, keep in mind that this look is not ideal for high-traffic areas because of the dust and dirt that will inevitably get on the curtains.
Measuring the Width
Now that you have the length decided, you need to know how wide the panels need to be. We recommend measuring from the left curtain rod bracket to the right curtain rod bracket. Double that number to ensure fullness while open and plenty of coverage while the curtains are closed. That's the total width you will need to cover your window.
Keep in mind, some window curtains are sold by the pair, while others are sold by the single panel. Always read the product description or product packaging to be sure you are buying the right number of panels or panel sets for your space. Again, you don't want to be stuck with inadequate coverage or the hassle of having to return extra panels.
Now that you know how to measure for the size that you need, the best tip we can give you is to measure twice to confirm that you are getting it right.