Before installing any shutters, you need to ensure they fit right. To ensure it fits well and matches the design to the core, the first thing is to measure everything perfectly. When measuring your shutters, you need to find different and creative ways to make it work – if it's to work.

You can use several ways to measure large windows for exterior shutters. Each of them will lead you to the final destination, making the shutters fit. You need to figure out which one works best for your particular needs.

Here are some of the top ways to measure for windows and how to measure for shutters that'll fit. 

Determine What You Want to Cover on the Window

Before you measure the height or width of your window, you will need to determine what your shutters will cover. Most people choose to cover their entire frame, but some options are available if you prefer not to cover the whole window. Some will look at the overall exterior décor of the windows.

  • If you want to cover the entire wall, measure from the floor to the ceiling and then from one side of the opening to the other. You do not have to worry about any obstructions such as moldings because you are starting at each end of the opening and measuring over.
  • If your window is not square, take separate measurements for each side.
  • If you want only to cover a portion of your wall or window frame, measure from where you want one side to end over however much space you would like covered (at least 1/4 inch but no more than 1/2 inch), and then down however much space you would also like covered (this measurement should be at least 3 inches). Remember that it's best practice not to exceed half an inch between each shutter panel so they can open independently and properly support themselves with hinges attached securely on both sides.

Measure the Height of the Window

You can measure the window's height on the left, middle, and right. Measure from the top of the window to the bottom of the window. If your window is not square (perfectly flat), you will use the smallest measurement as your finished height.

Measure from left to right at three different heights on each side:

  • top - measure from left to right at the top crosshead
  • middle - measure from left to right at the middle crosshead
  • bottom - measure from left to right at the bottom crosshead

If you have swag above your windows, it's best to add a few extra inches to cover when installing the shutters. To find out if you have swag, stand outside and see where your window trim meets up with your siding.

Measure the width of the Window

Next, measure the width of the window.

You will need to take measurements from three different spots on the window: top, middle, and bottom. It would help to record the smallest width measurement and then order shutters based on that exact measurement. For example, if you have a 35-inch window, but it measures 34 inches at its narrowest point (usually at the top or bottom), you'll want to order custom shutters designed for a 34-inch window.

You can use either a tape measure or a laser measuring device to find your smallest width measurement. Do not rely on your eye — using an actual measuring device is critical to ensuring an accurate fit. You want everything to fit in right when you finish setting up what you are covering. 

Decide How Much You Want to Cover the Window

If you want to get outdoor shutters to fit your windows, you need to measure the window.

There are many different types of shutters, but the most commonly used ones are commonly known as 'louver' or 'raised-panel' shutters. Some may also use shutter names like tier-on-tier, board and batten, and panel. Though there are many more kinds of shutters in the world, these four should be enough for most home renovations. To measure a window for these types of shutters:

  • Get an accurate measuring tape and measure around the window where it meets with the wall precisely on its inner edge.
  • Ensure all trim pieces such as moldings and openings like keyholes or pocket doors.
  • Measure from the wall across to the outer edge of the window, which is usually made from wood or metal panels. If you're measuring a single small window (less than 24 inches), measure between two vertical supports on either side of the window, usually made from wood or metal panels.

Subtract ¼ inch from Each Side of Your Measurements for an Overlap

Remember to subtract ¼ inch from the measurement you took so that the decorative shutter's exterior will fit inside the frame. Shutters should have some wiggle room to close, but they should not be so big that they cover your window when closed.

If you forget this step, you might have to pay for a new set of shutters. If you are worried about whether or not your measurements are correct, we recommend measuring twice before starting your order.

These Steps Will Help You Measure for Exterior Shutters

Before you can even think about picking the right shutters, you need to measure your windows. You'll want to get an exact measurement of your windows before choosing a shutter for your home. You'll need a measuring tape or ruler and notebook to do this. Make sure that you record each measurement with the width and height of each window and which room it's in.

You can measure your windows with a tape measure or use an app with a ruler tool on your phone. The next step is to take those measurements and turn them into usable data so you can choose custom shutters for your home.


If you get it right with your shutters, you need to ensure that your measurements are on point. Use any of the above ideas to measure large windows for exterior shutters. The one that works fits perfectly for the overall exterior design of your home.