How to Weigh Your Child at Home (and Know If It's Normal)

Medically reviewed by Dr. Rafia Rashid — FCPS (Pediatrics), FCPS (Pediatric Gastroenterology & Nutrition)

To weigh your child correctly at home, use the same digital scale every time, on a hard flat floor, with your child in light clothing or a dry diaper, at about the same time of day. Then compare the number with a growth chart, not just with last month's number. One reading means little; the trend across visits is what matters.

Why accurate weight matters

Growth tracking is one of the simplest ways to catch a problem early. A child who is feeding poorly, absorbing nutrients poorly, or fighting an ongoing illness often shows it on the growth chart before any other symptom appears. But a small measuring error — a wet diaper, an uneven floor, a different scale — can shift the number enough to trigger a false alarm or hide a real one.

Choosing a scale

• Under 2 years: an infant scale is the most accurate, but few homes have one. For babies, the weights taken at check-ups and vaccination visits are the most reliable record.
• 2 years and older: use a flat digital scale, ideally one with a "tare" (zero) button. Avoid old spring-loaded bathroom scales — they drift and are hard to read accurately.
• No scale at home? That's fine. Your child's regular check-ups and vaccination visits are a good time to get an accurate weight.

Step by step

Babies and toddlers (under 2 years)

• Weigh in a dry diaper only, or naked.
• Keep the baby still for a few seconds; if they move, take two readings and average them.
• Length is measured lying flat and needs two people and a firm, flat surface: one holds the head gently against a wall or board, the other straightens the legs and marks the heel. If you can't do this easily, leave length to your clinic visit.

Children 2 years and older

• Remove shoes, socks, and heavy or wet clothing.
• Stand with both feet flat in the centre of the scale, without holding onto anything.
• Measure standing height against a wall: heels, buttocks and the back of the head touching the wall, eyes looking straight ahead, with a flat book resting on the crown.

If your toddler won't stay still on the scale

• With a tare button: stand on the scale, press tare so it reads zero, then take your child in your arms — the scale shows your child's weight.
• Without one: weigh yourself, then weigh yourself holding your child, and subtract.
• Either way, this gives an estimate, not an exact weight. It's fine for a rough check, but not for closely tracking a baby's weight gain — use the clinic's reading for that.

Common mistakes to avoid: weighing on carpet or a soft surface, right after a big meal, or on different scales and comparing the numbers — and reacting to normal day-to-day ups and downs.

Reading the number

CGC uses the WHO Child Growth Standards for children under 5 and the WHO Growth Reference for ages 5–19 — the same charts built into our growth tools. A percentile compares your child with 100 healthy children of the same age and sex: the 50th percentile means right in the middle; the 15th means about 15 in 100 children weigh less. A weight in kilograms means little on its own. What matters is where your child sits on the curve and whether they stay near that line over time. Some shifting is normal in the first two years; a percentile that keeps drifting away from its usual line across two or more visits is worth discussing with your doctor.

Track it with CGC's free tools

• WHO Growth Calculator — plots weight-for-age, length-for-age, or height-for-age against WHO charts, for children 0–10 years.
• BMI-for-Age Calculator — for children 5–18 years, using WHO BMI-for-age percentiles.

The BMI Calculator uses the WHO reference for school-age children and teens, so it starts at age 5; for younger children, whether weight is in proportion to length is best checked by your doctor. Both tools show where your child sits on the WHO curve — they don't diagnose, so if a result worries you, bring it to a consultation.

When to see a doctor

Book a check-up with your pediatrician or with us if you notice:

• Weight that stays flat or drops across two or more check-ups.
• A drop across two or more of the main percentile lines on the chart (for example, from above the 50th to below the 15th), or a reading below the 3rd percentile.
• Poor feeding, ongoing vomiting, or persistent diarrhea alongside a weight change.
• Unexplained weight loss over several weeks in a child who isn't otherwise sick.

Get care the same day, or go to the nearest emergency, if your child has vomiting or diarrhea and:

• passes much less urine than usual, or has a dry mouth, no tears, or sunken eyes,
• is very sleepy, floppy, or hard to wake,
• refuses to feed or drink,
• has green or bloody vomit, or blood in the stool, or
• is a baby under 3 months who is vomiting or not feeding well.

FAQ

How do I know if my child's weight is normal for their age?
Enter your child's weight, height or length, date of birth and sex in our Growth Calculator (up to 10 years) or BMI Calculator (5–18 years) to see their percentile. A single percentile isn't a verdict — steady growth along their own curve matters most, and your doctor can tell you what your child's result means.

What's the best time to weigh my child?
For older children, morning, after passing urine and before breakfast, tends to be the most consistent. For babies, who feed around the clock, weigh at the same point in the feeding cycle. Whatever you choose, keep it the same each time.

Why does my child's weight at home differ from the clinic's reading?
Different scales, different clothing, and a different time of day all shift the number a little — one study comparing home and clinic measurements found home weights tended to run slightly lower. This is expected. For the clinic record, always go by the reading taken on the clinic's scale.

Why does my child's weight go up and down every day?
In older children, weight naturally shifts by a few hundred grams with fluids, meals, and bowel movements. Small daily swings aren't meaningful — the trend over weeks and months is what to watch. The exception is weight loss with vomiting or diarrhea; see the same-day signs above.

How often should I weigh my child at home?
Healthy children who are growing well don't need routine home weighing — regular check-ups are enough. If your doctor asks you to monitor weight, follow their schedule. For school-age children and teens, weigh privately, avoid comments about body size, and let the doctor discuss the results.

Is it normal for a newborn to lose weight in the first few days?
Yes, newborns may lose some weight in the first few days after birth, and then gain it back. If you're unsure whether your baby's weight loss is normal, or your baby isn't feeding well, check with your pediatrician.

My child dropped a percentile. Should I worry?
A small shift is common and usually not a concern. Track the trend over two or three visits rather than reacting to one change, and talk to your doctor if the percentile keeps moving in one direction.

A note from Dr. Rafia Rashid

Accurate, consistent measurement is one of the most useful things a parent can do between clinic visits — it's why we built our free growth tools, so you can follow your child's numbers on the same charts we use. If anything about your child's growth concerns you, talk to your pediatrician or book a consultation with us, and we'll go through it together.

References

1. WHO. Training Course on Child Growth Assessment, Module B, "Measuring a Child's Growth" (2008). who.int/publications/i/item/9789241595070
2. WHO Child Growth Standards (0–5 years). who.int/tools/child-growth-standards
3. de Onis M, et al. Development of a WHO growth reference for school-aged children and adolescents. Bull World Health Organ 2007;85:660–7.
4. CDC. Growth chart training — recommendation to use WHO growth charts for children under 2. cdc.gov/growth-chart-training
5. SickKids AboutKidsHealth. How to accurately measure a child's height and weight at home.
6. Home vs. clinic measurement study, PMC8444654 (cited briefly for the home-vs-clinic difference only).
7. Golden NH, et al. Preventing Obesity and Eating Disorders in Adolescents. Pediatrics 2016;138(3):e20161649.

This article is for general information and does not replace individual medical advice.