Body Surface Area Formulas and Age Applicability
These formulas were developed in different study populations. Especially in pediatrics or unusual body composition, do not choose a dosing formula from this comparison alone.
Six methods for estimating body surface area (BSA) from height and weight. This is a formula reference, not a patient-data calculator.
Inputs: height in cm, weight in kg. Output: m². Fujimoto originally reported cm²; divide by 10,000 to express m².
| Formula | Age and study population | BSA (m²) |
|---|---|---|
| Mosteller (1987) | A single age applicability limit has not been established.Simple published approximation; age-specific validation population not confirmed from full original text. | √(height(cm) × weight(kg) ÷ 3600) |
| Du Bois and Du Bois (1916) | Not verified for the full pediatric population.Early height-weight relationship derived from a limited anthropometric sample. | 0.007184 × height(cm)^0.725 × weight(kg)^0.425 |
| Haycock (1978) | Premature infants, infants, children, and adults in the source study.Regression from measured body surface areas in 81 subjects including premature infants and adults. | 0.024265 × height(cm)^0.3964 × weight(kg)^0.5378 |
| Fujimoto et al. (1968), infancy | Under 1 year of age.Infant group within a Japanese study of 201 male and female subjects across ages. | (95.68 × weight(kg)^0.473 × height(cm)^0.655) ÷ 10000 |
| Fujimoto et al. (1968), ages 1–5 | Ages 1–5 years.Early-childhood group from the same 201-person Japanese study. | (381.89 × weight(kg)^0.423 × height(cm)^0.362) ÷ 10000 |
| Fujimoto et al. (1968), ages 6+ | Age 6 years or older.Older-child-to-adult group from the same 201-person Japanese study. | (88.83 × weight(kg)^0.444 × height(cm)^0.663) ÷ 10000 |
Worked examples (hypothetical)
Individual examples for each formula, rounded to three decimal places. Not dosing or diagnostic guidance.
| Method | Height | Weight | BSA |
|---|---|---|---|
| Mosteller (1987) | 170 cm | 65 kg | 1.752 m² |
| Du Bois and Du Bois (1916) | 170 cm | 65 kg | 1.754 m² |
| Haycock (1978) | 50 cm | 3 kg | 0.207 m² |
| Fujimoto et al. (1968), infancy | 50 cm | 3 kg | 0.209 m² |
| Fujimoto et al. (1968), ages 1–5 | 95 cm | 14 kg | 0.606 m² |
| Fujimoto et al. (1968), ages 6+ | 170 cm | 65 kg | 1.707 m² |
Method differences, original sources, and limitations
How to select a method
All formulas are estimates, not direct BSA measurements. Confirm the method required by clinical protocols. Accuracy in obesity, edema, pregnancy, limb loss or populations different from those studied is not established by this page.
Evidence and cautions
- Mosteller (1987): Original bibliographic record and later comparative papers were checked; original full-text coefficients and population still require verification. Original publication
- Du Bois and Du Bois (1916): Haycock and colleagues noted possible underestimation at small body surface areas. Original publication
- Haycock (1978): Fits its original population; accuracy for every body type and medical condition is not guaranteed. Original publication
- Fujimoto et al. (1968), infancy: Original S values are in cm²; divide by 10,000 for m². Validation for individual neonatal conditions remains unreviewed. Original publication
- Fujimoto et al. (1968), ages 1–5: Original S is in cm²; divide by 10,000. Model selection at age 6 has not undergone clinical review. Original publication
- Fujimoto et al. (1968), ages 6+: The original paper expressly states age 6+; original S is in cm² and is divided by 10,000 for m². Original publication
Verification and approval
Full original Mosteller text has not yet been checked for its population and coefficients; the other references were compared with available originals/abstracts. Formula verification does not equal clinical approval. Sources checked: 2026-11-10.