TBSA Calculator (Rule of Nines)
Estimate adult total body surface area burned using the Rule of Nines, with pediatric warning to use Lund-Browder or local burn charts.
Understanding this tool
Why nurses use it
Total body surface area (TBSA) burned drives fluid resuscitation (Parkland), referral criteria, and burn centre transfer decisions. Rule of Nines gives a rapid adult estimate by body region.
When to use it
Use in adult thermal burns before Parkland calculations — add palm method (≈1%) for scattered burns. For children, use Lund-Browder or local pediatric charts.
Calculate
How to use this calculator
- Select adult (child option directs to pediatric chart).
- Tick each body region involved.
- Sum % TBSA and document burn depth separately.
How the calculation works
Adult Rule of Nines (ABA): head/neck 9%, each arm 9%, each leg 18%, anterior trunk 18%, posterior trunk 18%, perineum 1% — total 100%.
Formula used by this tool — verify units before applying at the bedside.
Worked example
Limitations & clinical notes
- Adult Rule of Nines: head/neck 9%, each arm 9%, each leg 18%, anterior trunk 18%, posterior trunk 18%, perineum 1%.
- Children require Lund-Browder or local pediatric charts — do not use adult Rule of Nines.
- Palm ≈1% TBSA for scattered burns not covered by rule of nines.
References
Key sources: ABA — Guidelines for burn patient referral.
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Disclaimer: This calculator is for educational and bedside double-check purposes only. It does not replace institutional protocols, prescriber orders, pharmacist verification, or clinical judgment. Always follow your local policies — especially for high-risk medications, infusions, pediatrics, and critical care. If the patient is acutely unwell, escalate immediately rather than relying on any calculator output.