Rule of nines and Lund–Browder burn calculator
For healthcare professionals and students. Check results against your local protocols and clinical judgement; this tool does not give medical advice.
Burn size is expressed as a percentage of total body surface area (%TBSA). This calculator lets you shade the burned areas on a front-and-back body chart and adds them up two ways: with the Lund–Browder chart, which adjusts the head, thighs and lower legs for age from birth to adulthood, and with the adult rule of nines. Shade whole regions or half regions, or type exact fractions in the region table.
It is built for emergency, burns and paediatric staff and for students learning to estimate burn size. The chart, the table and the sums run entirely in your browser.
How to use the Burn TBSA Calculator (Rule of Nines & Lund-Browder)
- Choose Lund–Browder and the patient’s age, or Rule of nines (adult).
- Pick a brush: Full region, Half region or Unmark.
- Tap the burned regions on the front and back figures — the front figure faces you, so the patient’s right is on your left.
- For more precise shading, open the region table and choose ¼, ½, ¾ or all for each region.
- Read the total %TBSA, the front and back subtotals, and the notes. Use Clear chart to start again.
Burn TBSA Calculator (Rule of Nines & Lund-Browder) features
Clickable body chart
Thirty-three regions drawn front and back, usable by mouse, touch and keyboard (Tab then Enter).
Lund–Browder by age
Six age columns — birth, 1–4, 5–9, 10–14, 15 and adult — change the head, thigh and lower-leg values.
Rule of nines
Adult 9% blocks: head and neck, each arm, front and back of each leg, front and back trunk and 1% perineum.
Fractions
Half-region brush plus ¼–¾ choices in the table, because real burns rarely cover a whole region.
Checks
Every chart column is verified to total 100% in the self-test.
The rule of nines
Introduced in print by Wallace AB, “The exposure treatment of burns”, Lancet 1951;257(6653):501–504, after Pulaski and Tennison, the rule divides an adult body into areas of 9%: head and neck 9%, each arm 9%, the front of the trunk 18%, the back of the trunk 18%, each leg 18%, and the perineum 1%. It is quick but coarse, and it overestimates the legs and underestimates the head in children, whose heads are proportionally larger. Variants for infants exist, but published versions disagree on the leg values, so this tool uses Lund–Browder for children instead.
Lund–Browder chart values
Bittner EA, Shank E, Woodson L, Martyn JAJ, Anesthesiology 2015;122(2):448–464 tabulates the chart from Lund CC and Browder NC, Surg Gynecol Obstet 1944;79:352–358. Neck 2%, each trunk surface 13%, each buttock 2½%, genitalia 1%, each upper arm 4%, each lower arm 3%, each hand 2½% and each foot 3½% are the same at every age (half on each surface in the drawing); these change:
| Region (whole, one side) | Birth | 1–4 | 5–9 | 10–14 | 15 | Adult |
|---|---|---|---|---|---|---|
| Head | 19 | 17 | 13 | 11 | 9 | 7 |
| Each thigh | 5½ | 6½ | 8 | 8½ | 9 | 9½ |
| Each lower leg | 5 | 5 | 5½ | 6 | 6½ | 7 |
Using the estimate
- Count only partial- and full-thickness burns. Simple erythema is excluded; the review by Miminas (Wounds UK 2007;3(3):58–68) attributes many chart errors to counting it.
- Printed charts differ slightly. Some Lund–Browder drawings label each hand surface 1½%, which makes the figure add up to 101%. This tool uses 1¼% per surface (2½% per hand), as in the tabulated chart, so every column totals 100%.
- Small or scattered burns are often measured using the patient’s own hand surface as the unit — one of the three accepted methods listed by Miminas, citing Perry et al. and Rossiter et al. (1996). The hand’s exact share of body surface varies between people, so use your service’s convention.
- Fluid resuscitation formulas such as the Parkland formula use the %TBSA from this estimate together with weight; follow your burns service’s protocol and referral criteria.
- Re-estimate after cleaning and debridement, and compare with a second assessor when the number drives treatment.
Burn TBSA Calculator (Rule of Nines & Lund-Browder) FAQ
What is the rule of nines?
A quick way to estimate burn size in adults: the head and neck, each arm and the front and back of each leg are 9% each, the front and back of the trunk 18% each, and the perineum 1%. This rule of nines calculator adds the areas you tap.
How is the rule of nines different for a child?
Children have larger heads and smaller legs relative to their bodies, so the adult rule is inaccurate. The Lund–Browder chart adjusts for age — for example the head is 19% at birth and 7% in an adult — and is the method used for children here.
How do I calculate TBSA for a burn?
Shade each burned region, estimate what fraction of the region is burned, multiply by the region’s percentage and add them up. The calculator does the multiplication and the sum.
Should superficial burns be included?
No. Simple erythema (superficial, epidermal burns, such as typical sunburn) is not counted in %TBSA.
Which is more accurate, rule of nines or Lund–Browder?
The Lund–Browder chart is generally regarded as the more accurate, especially in children; the rule of nines is faster for a first estimate in adults.
Is there a rule of nines diagram I can print?
The body chart on this page is the diagram; use your browser’s print command to print the page with your markings.