How to Measure a Transom Angle

Transom angle is a standard boating measurement.

Transom angle measures the angle of a boat's stern relative to the bottom of the boat. You may need to collect data on the transom angle of your boat when reselling it or cataloging information about it. The measurement of a boat's transom angle requires a relatively simple calculation, but consult the Resources section of this article to use an online tool to calculate the transom angle for you.

Things You'll Need

• Boat
• Carpenter's square

Instructions

1. Take your carpenter's square and place the long side against the keel.

2. Slide the carpenter's square until the short end of the square touches the transom.

3. Measure the distance between the inside corner of the square and the bottom of the boat.

4. Count the number of quarter inches in your measurement. For example, if the distance measured in Step 3 was 5 inches, you would have 20 quarter inches measured.

5. Convert the number of quarter inches to degrees. Each quarter inch measured equals one degree in transom angle, so in our example your transom angle equals 20 degrees.

References

• Seamount-mattson.com: Transom angle measurement
• Johnsonbimini.com: Measuring your boat

Resources

• Rocketflap.com: Online transom angle calculator
• Almiyachts.com: Boat measurement tips