Burn Percentage Calculator (Rule of Nines)
Result
Burn Percentage Calculator (Rule of Nines) Estimate the total body surface area (TBSA) burned in an adult using the Rule of Nines. Mark each affected body region to add up the percentage burned — a fast emergency estimate used to guide fluid resuscitation — free online calculator.
Formula
- Burn Percentage Calculator (Rule of Nines) calculates its result from Head/neck (%), One arm (%), Anterior trunk (%), Posterior trunk (%), One leg (%), Perineum (%). It uses the formula The Rule of Nines divides an adult body into areas that are multiples of 9% of total surface area.Head and neck = 9%, each arm = 9%, each leg = 18%, front trunk = 18%, back trunk = 18%, genitalia = 1%.Select each region that is burned and the percentages add up to the total TBSA.A TBSA of about 15% or more in adults often signals the need for IV fluid resuscitation.Children have different proportions (larger heads), so the adult Rule of Nines doesn't apply to them.. Change any input to recalculate the result instantly. This is an informational calculation and is not medical advice.
- The main inputs are Head/neck, One arm, Anterior trunk, Posterior trunk, One leg, Perineum. Enter them in the units and format shown in the calculator.
- Use the measurement units shown beside each field. The result is an estimate and should be interpreted in context.
- Changing any input above recalculates the result with the same calculation engine used by this page.
Example: Burn Percentage Calculator (Rule of Nines)
- Head/neck: 9 %
- One arm: 9 %
- Anterior trunk: 18 %
- Posterior trunk: 18 %
- One leg: 18 %
- Perineum: 1 %
Using Head/neck (%) = 9, One arm (%) = 9, Anterior trunk (%) = 18, Posterior trunk (%) = 18, One leg (%) = 18, Perineum (%) = 1, the calculated result is 73.
Sample result: Calculating…
Frequently asked questions
What does the Burn Percentage Calculator (Rule of Nines) calculate?
Burn Percentage Calculator (Rule of Nines) Estimate the total body surface area (TBSA) burned in an adult using the Rule of Nines. Mark each affected body region to add up the percentage burned — a fast emergency estimate used to guide fluid resuscitation — free online calculator.
Which values should I enter?
Enter Head/neck, One arm, Anterior trunk, Posterior trunk, One leg, Perineum using the units and format shown beside each field.
What formula does this calculator use?
The calculator uses the following relationship: The Rule of Nines divides an adult body into areas that are multiples of 9% of total surface area.Head and neck = 9%, each arm = 9%, each leg = 18%, front trunk = 18%, back trunk = 18%, genitalia = 1%.Select each region that is burned and the percentages add up to the total TBSA.A TBSA of about 15% or more in adults often signals the need for IV fluid resuscitation.Children have different proportions (larger heads), so the adult Rule of Nines doesn't apply to them..
Why might my result differ from another source?
Results can differ because measurement methods, rounding and assumptions vary. This calculator is an estimate and is not a medical diagnosis.
Does the result update automatically?
Yes. Changing an input updates the result using the same calculation engine shown on this page.