How to weigh yourself

A scale gives you one number. It jumps around, it's easy to misread, and sometimes it just ruins your mood. Here's how to get something useful out of it without the worry.

Information checked on 2026-09-30. General information, not medical advice. How we calculate

In short: your weight moves 1–2 kg a day. Weigh under similar conditions and look at the trend (a weekly or two-weekly average), not one number. If the scale makes you anxious, or you have a history of eating disorders, it is perfectly fine to avoid it.

Why the number jumps around

Weight isn't just fat. It's muscle, bone, water and whatever is in your gut at the moment. So it easily changes by 1–2 kg in a day, and that says nothing about fat. Common reasons:

  • Salt and carbohydrate. Saltier or carb-heavy food holds on to water.
  • What you eat and drink. A litre of fluid temporarily adds about a kilogram.
  • Digestion. Constipation or a recent dinner adds weight.
  • A new or harder workout. Muscles temporarily hold more water.
  • The menstrual cycle. Many women weigh more for a few days before or during a period because of water.

How to weigh so the numbers are comparable

  1. At the same time of day – usually in the morning.
  2. After the toilet and before eating and drinking.
  3. In similar clothes (or none).
  4. On the same scale, on a flat, hard floor – not a carpet.
  5. Write the number down. One reading says almost nothing; a series of them shows a direction.

Look at the trend, not one day

The simplest way is a weekly average. If you weigh daily, add up the week's numbers and divide by how many you have. Compare that with the previous week's average. If you weigh once a week, look at the course over several weeks. A clear direction often only appears after 2–3 weeks.

Weight not moving for a few weeks? Before drawing conclusions, read Why isn't my weight going down, even though I eat less?

Your waist as a second signal

A scale doesn't show where weight sits. So it can help to measure your waist every few weeks too (around the middle of your belly, halfway between your lowest rib and your hip bone, relaxed). Commonly used cut-offs: a waist from 94 cm for men and from 80 cm for women suggests a raised health risk, and from 102 cm for men and 88 cm for women a higher one. These are general cut-offs, they can differ by ethnic background and age, and they aren't a diagnosis. There's more in our BMI guide.

When it's better to skip the scale

A weight should help you, not hurt you. It's worth putting the scale away and talking to a doctor or a psychologist if:

  • you have or have had an eating disorder;
  • the number causes strong anxiety, guilt or shame, or a bad day because of it;
  • you weigh yourself many times a day or can't resist;
  • you restrict food or over-exercise because of the number.

In that case it's better to track other things: how you feel, your energy and how your clothes fit. The Dumpli nutrition quiz includes a short eating-disorder questionnaire (SCOFF), and your answers stay in your browser.

When to talk to a doctor first

Before you change how you eat to lose weight, talk to your doctor first if:

  • you are pregnant or breastfeeding;
  • you have diabetes or take medicines that affect your blood sugar;
  • you have kidney disease, heart disease or another long-term condition;
  • you are under 18;
  • you have or have had an eating disorder;
  • you are losing weight without trying.

If your relationship with food worries you, you can talk to a doctor or a psychologist. If you're struggling right now, call your local emergency number or find a free helpline at findahelpline.com.

Want the trend rather than a jumpy number? In the Dumpli app the weight chart shows your weigh-ins, a 7-day average and a band for where your plan says it's realistic to be. Dumpli Plus also compares your plan with your real trend every 2 weeks and suggests a change – you decide, and the safe limits apply to everyone. The app is still in testing and open by invitation. This guide is useful without it. See the app → · Take the nutrition quiz

Frequently asked questions

Why does my weight change every day?

A daily swing of 1–2 kg is normal. It comes from water, the salt and carbohydrate in your food, digestion and other things (and for many women, the menstrual cycle). It isn't a change in fat.

How often should I weigh myself?

Any frequency that doesn't bother you. Some people weigh daily and look at the weekly average; others weigh once a week. If the scale makes you anxious or is a chore, weigh less often or not at all.

What is the best time to weigh myself?

Under similar conditions each time: in the morning, after the toilet, before eating and drinking, in similar clothes (or none), on the same scale placed on a flat, hard floor.

Can my weight stay the same while my waist shrinks?

Yes, and it's a good sign. Body composition can change (less fat, more muscle or water) and a scale can't show that. Waist measurement is a useful second signal next to weight.

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