Most diets fail not because of willpower but because of missing numbers: how much you actually burn, and therefore how much you should eat. Spend three minutes calculating your baseline before copying anyone's meal plan.
BMR: The Calories You Burn Doing Nothing
Basal Metabolic Rate is the energy your body needs just to breathe, pump blood and stay warm — determined by height, weight, age and sex. Multiply it by an activity factor to get TDEE: sedentary ×1.2, light ×1.375, moderate ×1.55, intense ×1.725. To lose fat, eat 300-500 kcal below TDEE. Crash dieting below BMR eats your muscle and slows your metabolism, making every subsequent attempt harder.
Heart-Rate Zones: Aim Your Effort
- Max heart rate ≈ 220 − age; every zone builds on it.
- Warm-up zone (50-60%): waking the body up.
- Fat-burning zone (60-70%): highest fat contribution — brisk walking and easy jogging live here.
- Cardio zone (70-80%): builds aerobic capacity; runners' home turf.
- Anaerobic zone (80%+): glycogen-fueled and hard to sustain — interval training territory.
Movement and Water: The Other Two Ledgers
Exercise burn is estimated by MET values: jogging ≈ 8, jump rope ≈ 10, strolling ≈ 3 — multiplied by body weight and duration. The humbling result: 30 minutes of jogging burns roughly a milk tea's worth of calories. Water intake is weight-based: 30-40 ml per kg, so a 60 kg person needs about 1.8-2.4 L daily.
Recommended Tools
Water Intake Calculator
Find your recommended daily water intake based on body weight, in cups and bottles.
BMR Calculator
Calculate your Basal Metabolic Rate and daily calorie needs with the Mifflin-St Jeor formula.
Heart Rate Zones
Get your maximum heart rate and the five training zones for fat burn, cardio and more.
Exercise Calories
Estimate calories burned for walking, running, swimming and more using MET values.
Free online, images never leave your browser
FAQ
Does BMR change over time?
Yes — weight loss and aging lower it, while adding muscle raises it. Recalculate every 1-2 months during a cut and keep lifting weights to protect muscle.
Is lower intensity always better for fat loss?
Low intensity burns a higher percentage from fat but a smaller total; high intensity burns more overall plus afterburn. Pick the intensity you can sustain — consistency beats optimization.