How to measure curtains for your windows

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Curtains are a very important feature in the home. Not only do they provide protection from the elements and privacy, but they are also a great interior design opportunity. To ensure they look their best, however, you need to learn how to measure curtains the correct way.

There cannot be a standard rule for curtain measurement, as style, look, and the type of curtain all come into play. How do you know what size curtain you need? This handy guide will account for the main options so you are not left out in the cold and have a clear idea of how curtains are measured.

A beautiful window treatment brings style to your home, but the correct window and curtain measurements are vital to ensuring the best look. Read on to learn exactly how to determine the right size for your curtains and create a truly stunning feature for your interior.

Start by choosing a mounting technique

Outside mount curtain

The first step is deciding the mounting technique you will opt for. This is vital as you will need to know how to measure your windows for the right curtains. The key is deciding whether you want to mount your curtains outside or inside the window frame. These two options will create two very different aesthetics, so consider the look of them both before making a choice.

The two options can be broken down like this:

1. Outside Mount Curtains

This is the most common mounting style when it comes to hanging curtains. Curtains mounted outside of the window frame mean the rod is secured to the wall for support. This hanging style gives the illusion of a larger window, while also offering complete coverage which is far more effective at blocking out all of the natural light. This offers a more luxurious look for your interior.

2. Inside Mount Curtains

A little less common due to the specific look the inside mount creates, this method sees the curtain rod secured inside the window frame. This provides a more minimalistic and streamlined look. The one point that some may consider a downside is the fact that inside-mount curtains will not completely block out light. This option is better for those who wish to achieve a modern look.


See also: Drapes vs curtains: What’s the difference?


Next, you need to calculate the rod length

Measure for curtain rod length

The length of your curtain rod will typically extend 3 to 6 inches past the window frame. This will, however, depend on where you will be installing your rod. The options for rod installation include inside, below, or above the trim mount, and all of these options have a different effect on the length.

Here are the considerations you’ll need to make for each option:

  • Inside Trim Mount
    If you are aiming for a more streamlined look with suspended curtains from within the window frame, you’ll want curtain rods with protective end caps. You can choose a rod with an expandable design the right fit, and in keeping with the modern style, you’ll want your rod to be as wide as the interior of the window. You can go slightly wider if you want your curtains to have a gathered look.

  • Below Trim Mount
    Let’s say the top of your window frame has a design or look that you love and want to remain visible. Mounting your curtain rod below the trim will showcase the craftsmanship of your frame without sacrificing any privacy or style. In this case, you’ll aim for a rod that sits around 3 to 5 inches past the width of the window on both sides.

  • Above Trim Mount
    The most common placement is about 6-12 inches above the window frame. This is dependent on the available space present between the ceiling and the top of the window. Your curtains can be hung as high as 20 inches above the frame which will give a long look. The rule is the wider and higher your curtain rod is; the larger your window will look.

This next part is also dependent on the particular interior design you are going for. The right length needs to be considered with how you plan to hang your curtains and the various options which will create a varied look.

You can choose from the following:

  • Above Sill: Typically 1 cm above the windowsill.

  • Below Sill: Curtains that end roughly 15 cm below the windowsill

  • Floor Length: Dependent on style, the common option is curtains that end 1 cm above the floor

If you’d like to know how much it costs for dry cleaning curtains, visit our updated dry cleaning curtain price guide.

How to measure curtain width and length

Measuring length for curtain

How much wider should the curtains be than the window? The standard rule is that your curtains are about 1 1/2 to 3 times the width measurement of your window. This can vary based on the fullness you choose and style you want to achieve. If you have gone with fuller curtains, you’ll get a more decadent feel, whilst curtains with a shorter width give a more tailored look.

It’s always a good idea when buying curtains to ensure they come in a pair if the curtains are sold separately by “panel” you’ll need to double the listed width. You can use a tablecloth or blanket to compare full sizes.

When it comes to measuring the length, you’ll need to work out the distance from the bottom of the panel, to the rod pocket. Keep in mind that the length you choose will need to consider your hanging method and aspired look. Always place the measuring tape in the top inside corner of the window or at the top of the window frame and measure down to your desired length.

If you are dealing with a higher curtain placement, you’ll need to measure up from the top window frame by 20 inches to create an elongated look. 


See also: How much do curtain and blind fitting cost?


How to measure eyelet curtains

Measure for eyelet curtains

If you are looking to install eyelet curtains, they will need to be hung from curtain poles. To measure, simply find the size between the finials, or decorative ends, which will give you the width.

For the drop, the inner edge of the eyelet will be set down 3 cm from the top of the curtain. Allow for this when measuring to ensure that your curtains will not hang too short. Measure from the top of the pole all the way to where you would like the curtains to finish then add the 3 cm on top of that.

For example, if the finished drop from the top of the pole is 220 cm, your drop will actually be 223 cm. So you would order 223 cm eyelet-headed curtains.

Have fun decorating your space!

The right curtains can drastically change and improve the look and feel of a room. They certainly offer some functional benefits, but the design side is where the fun is! Double-check all of your measurements to ensure you’ve calculated the right sizes then enjoy picking your colour scheme.

Learning how to measure for curtains doesn’t need to be a chore. If you need a little help, the world of curtains can be significantly improved with a range of skilled taskers. You can find help with blind repairs, curtain rod installation, as well as general supply and assistance with installing curtains and blinds.


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Curtain Measurement FAQs

While it is somewhat dependent on the look and style of curtain you are aiming for and using, most curtains and window treatments require two to three times more material for those hoping for an amount of fullness in their curtain appearance. Start by measuring the width of your curtain rod from left to right; usually, the curtains' finished width should be at least double the width of your window for the standard curtain full look. It is important to note that this is applicable for a full curtain look, those after a more modern and minimalist style will keep their curtain measurement closer to the actual size of the window.

If you are buying ready-made curtains, they are usually sold in pairs. The size on the pack will tell you the measurement of one curtain lying flat. The individual sheets are often referred to as panels. The amount you require will be dependent on the size of your windows. Another factor to consider is the style of curtain you wish to have. Those aiming for the bunched, full look will often need to double the length of their window to achieve it. For a more minimalist look, you’ll keep your material size pretty close to the size of your windows.

When determining the size of your curtains, it is always advised that you use a metal tape measure. The width is always the first measurement provided. For example, 46” x 54” (117cm x 137cm) will tell you that each curtain is 46 inches (117cm) wide with a 54 inch (137cm) drop. There are a few other factors to consider, such as your mounting technique for the curtains and the specific style you hope to achieve. be sure to double-check all of your calculations before placing a made to measure order.

This depends on the curtain style you’ve chosen. Lengthy curtains can look stylish and elegant. These are best for rooms with tall windows. However, floor length curtains are not recommended if you have pets, as the bottom of the fabric can accumulate fur.

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