How to Measure the Size of a Door

Co-authored by Ryaan Tuttle

Last Updated: February 9, 2021

Determining the size of your door is as simple as taking a few measurements and doing some basic math. You just need to find the height and width of the door using a measuring tool. Once you have measured these accurately, you can start on whatever your home project is, like replacing the door, installing a new style door, or decorating the one you currently have.

Part 1

Part 1 of 2:

Taking Measurements

1
Measure the width of the door.^{[1]
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Expert Source

Ryaan Tuttle
Home Improvement Specialist
Expert Interview. 13 January 2021.} Run a tape measure along your door from the left corner to right corner, and record this number. It is important that you only measure the door. Do not include any other elements, such as weather-stripping.^{[2]
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- Particularly with older doors, it is important to measure in more than one location, just in case the door is not perfectly rectangular. If the amounts vary, use the largest figure.
- Door widths of 30 inches (76 cm), 32 inches (81 cm) and 36 inches (91 cm) are considered "standard."
2
Determine the height of the door.^{[3]
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Expert Source

Ryaan Tuttle
Home Improvement Specialist
Expert Interview. 13 January 2021.} Run your tape measure along your door from the top corner to the bottom corner, and write this number down. You may need to use a chair and/or ask a friend to help you. Once again, measure only the door itself and no other elements, such as a door sweep.^{[4]
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- Once again, it is wise to measure in more than one spot on the door, just in case it's not a perfect rectangle. This is especially true for older doors. If the amounts vary, use the largest figure.
- The most common height for doors is 80 inches (200 cm).
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3
Figure out the thickness of the door. Hold a tape measure to the edge of the door and record its thickness. Measure this edge on the door frame (known as the jamb), as well. These numbers should be close to the same, but it can be helpful to know both of them.^{[5]
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- The most common thickness is 1.75 inches (4.4 cm).
4
Measure the height and width of the framed door space. Just to be safe, measure the area where your door will go, too. Record the height and width of the door frame space. This will help ensure that you select the exact right replacement door.^{[6]
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- Measure the width of the door in 3 locations. Use the smallest figure as your measurement.
- Measure the height of the door right in the middle. Measure from the floor to the underside of the trim at the top of the door.
- If you must, it is always better to round down than round up. This helps to ensure that your door will fit.

Part 2

Part 2 of 2:

Creating a Diagram

1
Take a picture of your door and print it out. When you go in to select a replacement door, you should bring along a diagram with all relevant characteristics and measurements. One easy way to do this is to photograph your door and print out the image.
- You can also simply draw a diagram with paper and pen.
2
Label the swing direction of your door. Open your door. Position your body so that your back is against the hinges. If the door is on your right, it is a right-handed door. If the door is on your left, it is left-handed. Your door will also either be in-swing or out-swing. Determine both of these characteristics and record them on the diagram you made.^{[7]
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- An in-swing door opens into your house (or into a room), and an out-swing door opens outward.
3
Record all of the measurements on your diagram. Write the height, width, and thickness of your door down on your diagram. Write down the the height, width, and thickness of the door frame, as well.^{[8]
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4
Bring this diagram with you when you shop for doors. This diagram should make the process of replacing your door a lot simpler. Bring it with you any time you look at doors, and use it to guide your purchase.^{[9]
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Expert Q&A
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Question

How do I measure for a new door?

Ryaan Tuttle
Home Improvement Specialist
Ryaan Tuttle is a Home Improvement Specialist and the CEO of Best Handyman, Inc. in Boston, Massachusetts. With over 17 years of experience, he specializes in building home service businesses, focusing on creating scalable and efficient brands. With the help of his global team, the companies have achieved over 10+ million in sales and received recognition through magazine features, and enjoy partnerships with wikiHow and Jobber field service software. Boston Magazine and LocalBest.com have named Best Handyman Boston the Best Handyman in Boston. Ryaan holds Construction Supervisor and Home Improvement Contractor Licenses.

Ryaan Tuttle

Home Improvement Specialist

Expert Answer

Support wikiHow by unlocking this expert answer.

In order to measure for a new door or door slab, all you have to do is measure the width and the height of the door opening.
Question

How do I measure for a new door and a new door frame?

Ryaan Tuttle
Home Improvement Specialist
Ryaan Tuttle is a Home Improvement Specialist and the CEO of Best Handyman, Inc. in Boston, Massachusetts. With over 17 years of experience, he specializes in building home service businesses, focusing on creating scalable and efficient brands. With the help of his global team, the companies have achieved over 10+ million in sales and received recognition through magazine features, and enjoy partnerships with wikiHow and Jobber field service software. Boston Magazine and LocalBest.com have named Best Handyman Boston the Best Handyman in Boston. Ryaan holds Construction Supervisor and Home Improvement Contractor Licenses.

Ryaan Tuttle

Home Improvement Specialist

Expert Answer

Support wikiHow by unlocking this expert answer.

If you're going to measure for a new door and a frame, what you need to do is measure the door slab itself. That will tell you what size door and frame you need to replace it with.