How much weight can you lose in a month?
“How do I lose 10 kg in a month?” is one of the most common questions out there. The honest answer is less dramatic than the ads, but it's real: here's how much weight really comes off in a week, in a month, and how long 10 kg takes.
By the Dumpli team · Information checked on 2026-10-11. General information, not medical advice. Who writes this and how we check · How we calculate
🧮 Try it: Weight loss calculator – How long reaching your goal takes at a safe pace – a range, not a magic date.
How much weight really comes off in a week
Losing weight comes down to a calorie deficit: eating a bit less than you use. A kilogram of body fat holds roughly 7,700 kcal (a widely used approximation). So if you eat 500 kcal a day less than you use, that adds up to about 3,500 kcal a week – roughly half a kilo of fat.
Many health bodies (the UK's NHS, for example) mention about 0.5–1 kg a week as a safe upper limit. The Dumpli calorie calculator suggests even gentler paces, because they leave you less hungry and are more likely to last. How to work out your own deficit step by step is in our calorie deficit guide.
Why more seems to “go” in week one
In the first week the scale often shows a nice number – sometimes 1–2 kg. Most of that isn't fat but water: when you eat less, your body uses up its carbohydrate stores (glycogen), which are stored together with water. Part of it is also less food in your gut. That's normal and nothing bad – just don't expect that pace to continue.
How much in 2 weeks and in a month
Roughly, when you stick to the plan and leave out the first week's water:
| Pace per week | In 2 weeks | In a month | 10 kg would take |
|---|---|---|---|
| 0.25 kg | ~0.5 kg | ~1 kg | ~40 weeks |
| 0.4 kg | ~0.8 kg | ~1.7 kg | ~25 weeks |
| 0.5 kg | ~1 kg | ~2.2 kg | ~20 weeks |
| 1 kg (upper limit) | ~2 kg | ~4.3 kg | ~10 weeks |
In real life weight doesn't fall in a straight line: one week more, the next nothing, because water, salt, your menstrual cycle and sleep all move it around. Look at the trend over several weeks, not at one morning. How to weigh yourself so the numbers don't lie is in a separate guide.
Example: how long it takes to lose 10 kg
We worked these out with the same formula the Dumpli calorie calculator uses (Mifflin–St Jeor, an activity factor and safe minimums):
- Woman, 40, 165 cm, 85 kg, a bit active: uses about 2,090 kcal a day. The steady pace is about 1,670 kcal a day, which is roughly 0.38 kg a week. 10 kg takes about 26 weeks – around half a year.
- Man, 45, 180 cm, 100 kg, a bit active: uses about 2,620 kcal. The steady pace is about 2,100 kcal, roughly 0.48 kg a week. 10 kg takes about 21 weeks – around 5 months.
As your weight goes down, your body uses slightly less energy, so the pace slows over time. That's why it's realistic to plan with some slack: 10 kg in roughly 5–9 months. It doesn't sound fast, but those are 10 kg that are more likely to stay off.
Why “10 kg in a month” doesn't work
Losing 10 kg of fat in a month would take a deficit of about 77,000 kcal – around 2,500 kcal every day. For most people that's more than their entire daily need. Plans like that mean starving, and starving usually ends in:
- strong hunger and overeating after a few weeks;
- tiredness, poor sleep and irritability;
- losing muscle along with fat;
- weight coming back when “the diet is over”.
Very low calorie diets (for example, special meal replacements instead of food) are only for people whose doctor prescribes and supervises them.
What helps you keep the pace
- A small deficit you can repeat. Better 300–500 kcal every day than 1,000 kcal for three days and then giving up.
- Protein at every meal. It keeps you full and helps protect muscle – how much you need is worked out by the protein calculator.
- Moving every day. Not to “burn off” calories, but for your muscles, mood and appetite. How many calories walking really burns is in the calories burned calculator.
- Sleep. When you're short of sleep, you crave sweet food and eat more.
- Patience with plateaus. A few weeks without change are often water, not failure.
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.
Frequently asked questions
How much weight can you lose in a month?
At a safe pace, usually about 1–4 kg a month, depending on your starting weight and how much you move. A commonly quoted limit is up to 0.5–1 kg a week. Dumpli plans even more gently, around 0.25–0.5 kg a week, because that pace is easier to keep up.
Can you lose weight in a week or in 3 days?
The scale can show 1–2 kg less within a few days, but most of that is water and food in your gut, not fat. A kilogram of body fat takes roughly a 7,700 kcal deficit, so very little fat goes in a few days.
How long does it take to lose 10 kg?
For most people, about 5–9 months at a steady pace. For example, for a 40-year-old woman weighing 85 kg, our calculator's steady pace works out at about 0.38 kg a week – around 26 weeks – and the pace slows a little later on.
Why does weight drop fast in week one and then slow down?
When you start eating less, your body uses some of its carbohydrate stores (glycogen), which are stored with water. That water goes first. After that comes the real fat loss, which is slower but lasting.
Is losing weight fast harmful?
Very strict diets more often end in hunger, tiredness, muscle loss and weight coming back. Very low calorie diets are only for people under a doctor's care. A slower pace is usually the one you can actually keep.
Read next
- Calorie deficit: what it is and how much you need – How to work out a safe calorie deficit, why bigger isn't always better and when to review it.
- How many calories a day do women and men need? – Calorie needs by sex, age and activity (tables), how many to eat to lose weight, and why we never go below a safe minimum.
- How to keep weight off after losing it – Why weight creeps back, how to move to maintenance calories, how to read your weight trend, and what to do when it rises by 2 kg.