What weight-for-age tells you
A low weight-for-age result can reflect undernutrition, recent illness, feeding difficulty or inaccurate age entry. It should be interpreted with height and MUAC when possible because weight alone cannot separate stunting from wasting.
The full Poshan Calculator adds height-for-age and weight-for-height so the result becomes more useful for next steps. Use this page when a searcher specifically wants underweight screening or needs to understand why age in months matters.
Common mistakes
The most common errors are guessing age, mixing pounds with kilograms and weighing a child with heavy clothing. A one-month age error can change interpretation for young children, so birth date is better than memory where possible.
- Use completed months
- Use a calibrated scale
- Record the measurement date
- Recheck surprising results
What to do after a low result
A low result should lead to re-measurement and review of recent illness, appetite, feeding pattern and visible signs. If low weight repeats or appears with other warning signs, speak with a trained health worker.
