How to Measure Angles for Carpentry

Written by andrew latham Google
  • Share
  • Tweet
  • Share
  • Pin
  • Email
How to Measure Angles for Carpentry
If you are involved in a carpentry project, you will need to know how to measure angles accurately. (David Sacks/Lifesize/Getty Images)

Whether you are designing your own woodwork, building a replacement piece or trying to record the design of an existing item, you will need to learn how to measure angles for carpentry. There are a variety of tools you can use to measure angles in woodwork, depending on the size and precision requirements of the project. Two tools which are widely used in the measurement of angles are the protractor and the T-bevel. Both tools use similar principles and methods to measure angles.

Skill level:
Moderately Challenging

Other People Are Reading

Things you need

  • Protractor
  • T-Bevel
  • Carpenter's pencil.

Show MoreHide


  1. 1

    Choose whether you need to measure and mark a known angle or measure an unknown.

    This will determine the type of tool you need to use. For instance, if you need to mark a line at a certain angle, you should use a T-bevel. However, if you need to measure the angle of an existing design, you are better off using a protractor.

  2. 2

    Place the base of the T-bevel or protractor so it is parallel to the reference point of your angle, and so the small hole is over the point where the two lines join to make the angle.

    For example, if you want to measure the angle or slope of a roof on a drawing, place the base of your angle measuring tool along the base of the roof and the origin hole over the corner of the roof.

  3. 3

    Rotate the arm of the T-bevel or protractor so it matches the line that forms the angle you wish to measure.

    If you are using a protractor, you will need to rotate the arm until the reading of the protractor matches the existing angle. On the other hand, if you are using a T-bevel, you will need to rotate the T-bevel's arm until it matches the angle you need to mark.

  4. 4

    Draw the angle by sliding your pencil along the arm of the T-bevel.

    Using a protractor, write down the reading of the protractor to record the angle you measured in step 3.

Tips and warnings

  • If your project requires high levels of precision, invest in high quality measuring tools. Choose a T-bevel that has computer-guided etching to mark the angle scale. Choose a protractor that provides a digital reading of the angle, to minimise room for human error.
  • Second check all your measurements to avoid expensive mistakes.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.