Calorie deficit: the practical, science-based approach
1) Core idea
Weight loss happens when you eat fewer calories than you burn. The right deficit is safe, sustainable, and based on your BMR, activity, and goal rate.
2) Flow you can trust
- Enter your age, gender, height, weight, and activity level.
- Pick your goal weight and weekly loss rate.
- We calculate BMR (Mifflin, Harris, or Katch), TDEE, and a safe calorie deficit.
- See your daily/weekly deficit, timeline, and goal date.
3) Sanity checks
- 1 kg fat ≈ 7,700 kcal; 1 lb ≈ 3,500 kcal (for reference).
- Safe minimum: 1,200 kcal/day (women), 1,500 kcal/day (men) unless supervised.
- Exact conversions: 1 kg = 2.20462262185 lb; 1 in = 2.54 cm.
4) Shortcuts
- Moderate loss: 0.5 kg/week = ~250 kcal/day deficit.
- Use the built-in presets for BMR and activity multipliers.
- Recalculate every 5–10 kg lost or if activity changes.
5) Pitfalls
- Going too aggressive: large deficits slow metabolism and risk muscle loss.
- Not tracking intake accurately—use a food diary or app.
- Expecting linear progress: weight loss naturally fluctuates.
6) Micro examples
- 80 kg, 175 cm, 30y, male, moderate activity, 0.5 kg/week loss → ~2,150 kcal/day target.
- 70 kg, 160 cm, 40y, female, light activity, 0.25 kg/week loss → ~1,400 kcal/day target.
7) Mini‑FAQ
- Should I eat back exercise calories? If your TDEE includes exercise, no; if not, eat back 50–75% of exercise calories.
- Why isn’t weight dropping? Check tracking, water retention, and adjust as you lose weight.
- How often to recalculate? Every 5–10 kg lost or if your routine changes.
8) Action tip
Set a realistic weekly loss, use the calculator, and track your intake honestly. Adjust as you go—consistency beats perfection for long-term results.