How long is this actually going to take? Put in where you are and where you want to be. You get a date, the calories it needs, and a straight answer about whether the pace is sensible.
Nothing is sent anywhere - this runs inside your browser.
Enter your two weights and we will work out the date.
A kilo of body fat is commonly taken as roughly 7,700 calories. So losing half a kilo a week needs a gap of about 550 calories a day below what you burn. Divide the weight you want to lose by the weekly rate, and that is your number of weeks.
Treat 7,700 as a rule of thumb rather than a law. Real weight loss is never a straight line - water, food still in your gut and the time of the month all move the scale by a kilo or more in either direction. The date is a target, not an appointment.
Losing more than about 1% of your body weight a week is where things start going wrong. The gap gets big enough that your body takes a real share of it from muscle, and less muscle means a lower maintenance level, which makes the next stretch harder than the last. It is also the pace people quit at.
For most people 0.5 kg a week is the honest sweet spot. It is slow enough to hold together and fast enough to see.
Yes, and this is worth planning for. A lighter body burns fewer calories, so the same food that gave you a 550 calorie gap at 86 kg gives you a smaller one at 78 kg. Re-run the calorie calculator after every 5 kg and adjust. The date this page gives you assumes a steady rate, which real life only roughly obeys.
That is the useful part. Most people give up because they expected three months and it took nine - not because nine months was unreasonable. Seeing the real number up front is what makes it survivable. The calorie deficit guide covers what actually moves it.
A date from a formula assumes a steady rate, and bodies are not steady. Everything on this page is worked out from a formula or from published averages. It has never met you, and it cannot see your blood pressure, your medication or an old injury.
Talk to a doctor before you start if you are pregnant or breastfeeding, have a heart condition, diabetes or high blood pressure, take regular medication, have or have had an eating disorder, are recovering from injury or surgery, or are under 18. Stop and get advice if any exercise causes pain, dizziness or chest discomfort.
More about where these numbers come from is on the about page.
