Weight Loss Calculator
See how long it takes to reach your goal weight at a safe pace, from your current weight and a daily calorie deficit.
How Long Does It Take to Lose Weight?
Weight loss runs on two numbers: how much you want to lose and how big a calorie deficit you hold each day. A bigger deficit moves faster. A smaller one is gentler and easier to keep up. The right answer is the pace you can stick with.
Take a common goal of 10 kg. At a 500 kcal per day deficit you lose about 0.45 kg a week, so the trip takes about 22 weeks. That is roughly five months of steady effort. The calculator above turns your own weights and pace into a clear week count.
How the Math Works
A kilogram of body fat stores about 7700 kcal. To shed it, you spend more energy than you eat. The calculator finds the gap between your current weight and your goal weight, then divides that total energy by your daily deficit.
A 500 kcal daily deficit adds up to 3500 kcal a week, which is close to 0.45 kg of fat. Stack those weeks against your total and you get a timeline. To set your own deficit and maintenance level, start with the calorie deficit calculator and your TDEE.
Choosing a Safe Pace
The calculator shows four paces, from a 250 kcal Mild deficit to a 1000 kcal Maximum. Most people do well in the 250 to 500 kcal range, losing 0.25 to 0.45 kg a week. That feels slow on paper, but it protects muscle and is easy to hold for months.
Aggressive paces tempt you with faster numbers. The trade-off is more hunger, lower energy and a higher chance of quitting. To plan the daily intake behind your chosen pace, use the calorie calculator. Pick a pace you can live with, not the one that looks quickest.
Why the Scale Is Not a Straight Line
The formula assumes steady, linear fat loss. Real loss is bumpier. Water, sodium, food still moving through your gut and hormones all shift the scale from one day to the next. A flat week is normal. A small jump up is normal too.
Loss also slows as you get lighter, since a smaller body burns fewer calories at rest. Track the weekly average instead of single readings. The Velpa app logs your weight and steps in one private place so you can watch the trend and see whether your plan is working. This tool gives general information, not medical advice. Talk to a doctor before starting a steep deficit.
Frequently asked questions
- How long does it take to lose weight?
- It depends on how much you want to lose and your daily calorie deficit. At a 500 kcal per day deficit you lose about 0.45 kg (1 lb) a week. To drop 10 kg at that pace takes about 22 weeks. A larger deficit goes faster but is harder to keep up. Enter your weights above for your own timeline.
- How is the weight loss timeline calculated?
- A kilogram of body fat holds about 7700 kcal. The calculator works out the gap between your current weight and goal weight, then divides the total energy by your daily deficit. A 500 kcal daily deficit burns 3500 kcal a week, which is about 0.45 kg of fat. Spread across your total, that gives the number of weeks.
- What is a safe pace for weight loss?
- Most guidance points to 0.25 to 1 kg per week, which maps to a 250 to 1000 kcal daily deficit. The Mild and Moderate paces are easy to sustain for most people. Aggressive and Maximum paces are harder to hold and can cost you muscle. Pick a pace you can keep up for months, not days.
- Why is the scale not dropping in a straight line?
- The math assumes steady fat loss, but real bodies are messier. Water weight, food in your gut, hormones and sodium all move the scale day to day. Loss also slows as you get lighter because a smaller body burns fewer calories. Watch the weekly trend rather than any single morning.
- How much deficit do I need to lose 10 kg?
- At a 500 kcal per day deficit, losing 10 kg takes about 22 weeks. Double the deficit to 1000 kcal and the time roughly halves to about 11 weeks, though that pace is hard to sustain. A smaller 250 kcal deficit is gentler but slower. The calculator shows every pace so you can compare.