Calorie Deficit Calculator

1) Resting energy expenditure using the Mifflin–St Jeor formula: 10 × weight + 6.25 × height − 5 × age, plus 5 for men and minus 161 for women. 2) Multiply by your activity factor (from 1.2 to 1.725) to get maintenance calories. 3) Subtract the deficit: 1 kg of fat is about 7,700 kcal, so 0.5 kg per week is roughly 550 kcal per day. 4) Timeline is the weight difference divided by the pace. The "7,700 kcal per 1 kg" rule is a simplification: as you lose weight, your calorie burn decreases and weight loss slows down.

What calorie deficit is safe?

It is generally recommended to lose 0.5–1 kg per week, which corresponds to a deficit of about 500–1,000 kcal per day. Eating fewer than 1,200 kcal for women and 1,500 kcal for men is not recommended without medical supervision.

Why is weight loss slower than calculated?

As your body weight drops, energy expenditure decreases, and water retention fluctuates in the first weeks. Recalculate your target every 3–5 kg and monitor your trend over 2–3 weeks rather than day to day.

Do I need to count calories every day?

A deficit only works if it is maintained on average across the week. The easiest way is to log your food: in YaYo, you can simply take a photo of your plate, and calories and macros will be calculated automatically.