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Calorie Deficit Calculator

Get your personalized daily calorie target to lose weight at a safe, sustainable pace.

Daily calorie target

2,228cal/day

500 cal/day deficit · roughly 1.00 lb (0.45 kg) per week

Maintenance (TDEE):2,728 cal/day

How the calorie deficit works

Weight loss comes down to one principle: you have to consume fewer calories than your body burns. Eat 500 calories per day less than your TDEE for a week, and you create a 3,500-calorie weekly deficit — roughly 1 lb of body fat.

How to pick the right deficit

  • Mild (250 cal/day): ~0.5 lb/week. Easiest to stick to, ideal for the last few stubborn pounds.
  • Moderate (500 cal/day): ~1 lb/week. The sweet spot for most people — fast enough to be motivating, slow enough to preserve muscle.
  • Aggressive (1000 cal/day): ~2 lb/week. Works for those with more weight to lose, but harder to maintain and easier to over-shoot.

Smaller deficits are easier to sustain, easier to recover from on a bad day, and tend to preserve more muscle. Aggressive deficits can work — especially if you have a lot of weight to lose — but expect more hunger and a higher chance of plateau.

Tips that actually move the needle

  • Weigh and measure your food for the first 2–3 weeks — it's eye-opening.
  • Eat plenty of protein (around 1g per pound of bodyweight) to preserve muscle and stay full.
  • Pick a deficit you can stick to for 12+ weeks, not the most aggressive one.
  • Weigh yourself daily, but only look at the 7-day average — daily weight swings are mostly water.

Calorie deficit FAQs

What is a calorie deficit?+

A calorie deficit happens when you eat fewer calories than your body burns. When this happens consistently, your body taps into stored fat (and some muscle) to make up the difference, which results in weight loss.

How big of a calorie deficit should I have?+

For most people, a deficit of 300–500 calories per day is sustainable and produces 0.5–1 lb of weight loss per week. Deficits above 1000 calories/day work short-term but can cause muscle loss, low energy, hunger, and rebound eating.

How many calories are in 1 pound of fat?+

Roughly 3,500 calories — so a 500 calorie/day deficit produces about 1 lb of fat loss per week (3,500 ÷ 7 = 500). Note that real-world weight loss is messier than this clean math: water weight, glycogen, and metabolic adaptation all influence the scale.

Why am I not losing weight in a calorie deficit?+

Common reasons: (1) underestimating calories from cooking oils, drinks, or "bites and licks"; (2) overestimating activity multiplier; (3) water retention masking fat loss for 1–2 weeks; (4) metabolic adaptation after weeks of dieting. Track honestly for 2–3 weeks before adjusting.

What is the minimum number of calories I should eat?+

As a safety floor: ~1,200 cal/day for women and ~1,500 cal/day for men. Going lower long-term risks nutritional deficiencies, muscle loss, hormonal disruption, and rebound. If your calculated target is below those numbers, focus on activity or aim for a smaller deficit.

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