Curtain Size Calculator: The right size can make all the difference

Are you in the market for curtains? Before you click “buy” be sure that you’re getting the right size for your window. Curtains come in pretty standard sizes. Your job is to choose the size that is the closest to what’s ideal for your window.

Get a curtain that is too small/narrow and it looks like a mistake. Get the right sized curtain for your space and you’ll elevate your room.

Here’s an example from my own home. In the photo on the left, the curtains look too wimpy for the window vs the image on the right where the curtain is more substantial. There’s a 2 part formula to make sure you get the curtain that makes your space look warm and cozy.

Part 1 – How Long Should A Curtain Be?

The thing I realized after buying and making countless sets of drapes is that curtain rods are easier to move up and down than curtains are to hem. Standard curtain lengths are 72 inches, 84 inches, 96 inches and 108 inches.

These are the questions you need to answer before you choose the right length for you:

  • What is the distance from the top of your window to the floor?
  • How high are your ceilings?
  • Do you want curtains to barely touch the ground or pool on the ground?

Hanging your curtains HIGHER than you window sill makes you window look larger. Nothing looks worse than curtains that are too short. If your ceilings are 8 feet (96 inches), you will probably want to stick with 84 inch curtains.

Measure 4-6 inches above the window frame to the floor. This is the ideal height for rod which gives you the length for a curtain.

You will probably find this exact length is NOT a standard size. From there, adjust the curtain rod height to get to a length that IS available (you can see my favorite sources for drapes here). Add an extra 1-2 inches if you want the curtains to pool at the bottom.

Part 2 – How Wide Should A Curtain Be?

The rule of thumb is that your curtains should be 2 to 2.5 times as wide as your window. If you never plan to close the drapes, some would say 1.5 times is wide enough. This measurement works for a single panel if you want curtains only on one side of your window, or divide it by two for curtains on both sides.

curtain size guide

It can be tempting to settle for 1.5 times as wide as the window. Curtains are expensive and a 50 inch panel is much cheaper than a 100 inch panel. But the extra fabric adds a real feeling of luxury. I regret skimping in my bedroom thinking that I could always get new curtains. It’s been several years. Don’t skimp unless you don’t plan to use the curtains for very long.

It’s ALWAYS better to err on the side of too wide. The patterned curtain above is 1.5x the width of the window. The windows is 30 inches and the curtain is 45 inches. The curtain on the right is 2x as wide as the window.

How Wide Should Curtains Be For Two Windows ?

If you have two windows together, simply add the widths before applying the 2x rule. For example, two 30 inch windows are 60 inches wide. You would ideally want 120 inches of drapery.

Wait! Curtains don’t come in 120 inch widths (or even 60 if you are using a panel on each side). If you need 120 inches of fabric, ask yourself this question. Is this a room where I want a cozy feeling? More fabric makes a room feel more cozy and comfortable.

If it’s a bedroom, aim for at least 2x. If it’s a dining room or a kitchen, just under 2x is OK. It’s better to have 3x the width of your window than 1.5x if you want a cozy, warm look. To get this, purchase multiple panels and hang them together. You can get a 100 inch panel and 50 inch panel (in the example where I want 120 inches).

Buying curtains is probably not something you are going to do every year. Take the time to be sure the curtains you buy will stand the test of time. I’ve definitely learned from my mistakes in this area.

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  1. Andrea, I love these posts because they are SO informative! Iced in for a week! Yikes! And stop eating peanuts-how scary.. we have crows at our cabin and they are HUGE and a bit scary. After watching the movie The Birds you will need to share your crow knowledge with me. Happy Sunday!

  2. Great advice Andrea! I love your diagram with the measurements – I’m definitely a visual learner! 🙂 Love your stick blinds in the second picture too! You’re always so inspiring, my friend!

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