Topic Overview

You can quickly estimate the size of a burn by using the “rule of nines.” This method divides the body’s surface area into percentages.

Estimating burn size in adults

See a picture of the “rule of nines” for adults.

• The front and back of the head and neck equal 9% of the body’s surface area.
• The front and back of each arm and hand equal 9% of the body’s surface area.
• The chest equals 9% and the stomach equals 9% of the body’s surface area.
• The upper back equals 9% and the lower back equals 9% of the body’s surface area.
• The front and back of each leg and foot equal 18% of the body’s surface area.
• The groin area equals 1% of the body’s surface area.

Estimating burn size in babies and young children

See a picture of the “rule of nines” for babies and young children.

• The front and back of the head and neck are 21% of the body’s surface area.
• The front and back of each arm and hand are 10% of the body’s surface area.
• The chest and stomach are 13% of the body’s surface area.
• The back is 13% of the body’s surface area.
• The buttocks are 5% of the body’s surface area.
• The front and back of each leg and foot are 13.5% of the body’s surface area.
• The groin area is 1% of the body’s surface area.

The “rule of palm” is another way to estimate the size of a burn. The palm of the person who is burned (not fingers or wrist area) is about 1% of the body. Use the person’s palm to measure the body surface area burned.

It can be hard to estimate the size of a burn. If you think a burn is a certain size but you are unsure, it is best to discuss the size of the burn with your doctor.