Calorie Deficit Explained: The Simple Guide to Losing Weight

Every weight-loss strategy — low-carb, keto, intermittent fasting, portion control — works through one mechanism: a calorie deficit. You burn more energy than you eat. Once you understand it, dieting stops being confusing.

What Is a Calorie Deficit?

A calorie deficit is simply eating fewer calories than your body burns in a day. When that happens, your body uses stored fat for energy, and you lose weight. It's the same physics for everyone, regardless of diet.

How to Calculate Your Deficit

1. Find your maintenance calories — how much you burn per day (use our free calorie calculator)
2. Subtract 10–15% for a sustainable deficit
3. Example: maintenance 2,200 kcal → eat ~1,870–1,980 kcal

How Much Weight You'll Lose

A deficit of roughly 500 kcal per day equals about 0.5 kg (about 1 lb) per week. That's the sweet spot — noticeable progress without crash-diet suffering.

Common Mistakes That Kill Progress

• 🛑 Too big a deficit — starving yourself leads to muscle loss and rebound
• 🍰 Underestimating calories — sauces, drinks, and "small bites" add up fast
• ⚖️ Only cutting food, not tracking — guessing rarely works
• 🏋️ Ignoring protein and strength — you want fat loss, not muscle loss

Free to start. No app install, no credit card.

Also read: How Many Calories Should I Eat · How to Track Calories with AI