What is the Rule of Nines?

The Rule of Nines divides the adult body into regions each worth 9 percent of total body surface area or a multiple of nine: the head and each arm are 9 percent, the front and back of the trunk are 18 percent each, each leg is 18 percent, and the genitalia are 1 percent, totalling 100 percent.

Why use Lund-Browder for children?

Children have proportionally larger heads and smaller legs than adults, so the Rule of Nines overestimates leg burns and underestimates head burns in the young. The Lund-Browder chart adjusts the head and leg percentages by age band, making it the most accurate method, especially for infants and small children.

How does TBSA feed into the Parkland formula?

The Parkland formula estimates the first 24-hour fluid requirement as 4 mL multiplied by body weight in kilograms multiplied by percent TBSA burned. Half is given in the first 8 hours from the time of injury and the remaining half over the next 16 hours, then titrated to urine output.

Should I count superficial sunburn-type redness?

No. Only partial-thickness (second-degree) and full-thickness (third-degree) burns are counted towards TBSA. Superficial epidermal burns with erythema but no blistering, such as simple sunburn, are excluded because they do not drive significant fluid loss.

Is the palm method an alternative for small burns?

Yes. For small or patchy burns, the patient's own palm including fingers represents roughly 1 percent of their TBSA. That estimate is handy at the bedside, but for larger burns the Rule of Nines or Lund-Browder used here is more reliable.

What is the TBSA Burn Calculator (Rule of Nines & Lund-Browder)?

Calculate percent total body surface area burned using the Rule of Nines for adults or the age-adjusted Lund-Browder chart for children, then feed it straight into the Parkland fluid resuscitation formula. Runs entirely in your browser. It runs free in your browser on Gera Tools, with nothing uploaded.

TBSA Burn Calculator (Rule of Nines & Lund-Browder)

Name: TBSA Burn Calculator (Rule of Nines & Lund-Browder)
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

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Estimating burn size for resuscitation

The single most important number in early burn care is percent total body surface area burned — it drives fluid resuscitation volumes, transfer decisions, and prognostic estimates. This tool calculates TBSA two ways: the quick Rule of Nines for adults and the more precise, age-adjusted Lund-Browder chart for children, then feeds the result into the Parkland formula.

How it works

Each method assigns a maximum percentage to every body region. You enter how much of each region is affected by partial or full-thickness burns (0–100%), and the tool sums the weighted contributions:

region contribution = region_max × (fraction burned / 100)
TBSA               = sum of all region contributions

Rule of Nines (adults)

Region	TBSA %
Head and neck	9%
Each arm (whole)	9%
Anterior trunk	18%
Posterior trunk	18%
Each leg (whole)	18%
Perineum	1%

Lund-Browder adjustments by age

Children have proportionally larger heads and smaller legs. The Lund-Browder chart corrects for this by varying the head and leg allocations with age band:

Age band	Head %	Each thigh %	Each lower leg %
0–1 yr	19%	2.5%	2.5%
1–4 yr	17%	3.25%	2.5%
5–9 yr	13%	4%	2.75%
10–14 yr	11%	4.25%	3%
15 yr	9%	4.5%	3.25%
Adult	7%	4.75%	3.5%

The trunk, arms, and hands remain constant across all age bands. Using the Rule of Nines on a toddler can lead to overestimating leg involvement and underestimating head involvement — Lund-Browder removes this distortion.

Parkland formula

The Parkland formula estimates the first-24-hour crystalloid requirement for adults and children:

first 24 h volume = 4 mL × weight_kg × %TBSA   (lactated Ringer's or Hartmann's)
first 8 h         = half the total
next 16 h         = the remaining half

The 8-hour clock starts at time of injury, not time of arrival. Any fluid already given before the formula is applied counts toward the first-8-hour portion.

Worked example

A 70 kg adult arrives with a fully burned anterior trunk (18%) and one completely burned arm (9%), for a TBSA of 27%. Parkland estimate: 4 × 70 × 27 = 7,560 mL in the first 24 hours. Half of that (3,780 mL) is due in the first 8 hours from time of injury, roughly 470 mL/hr. The remaining 3,780 mL spreads over the next 16 hours, roughly 236 mL/hr.

What not to count

Count only partial-thickness (second-degree) and full-thickness (third-degree) burns. Superficial epidermal burns — where the skin is red but intact, without blistering — do not drive significant fluid loss and are excluded from the TBSA estimate.

Titration over the formula

The Parkland formula is a starting estimate, not a fixed prescription. Titrate infusion rate to maintain a urine output of 0.5–1.0 mL/kg/hr in adults (1 mL/kg/hr in children). Over-resuscitation drives oedema, abdominal compartment syndrome, and pulmonary complications. Use clinical response to adjust the rate up or down from the calculated starting point.