Losing weight comes down to eating fewer calories than you burn. Working out how many depends on two numbers: your maintenance calories, and how fast you want to lose.
Step 1: find your maintenance calories
Your maintenance calories, or total daily energy expenditure (TDEE), are what you burn in a day. They're your basal metabolic rate (BMR, the energy to keep you alive at rest) multiplied by an activity factor. Our calculators use the Mifflin-St Jeor equation, which research has found to be among the most accurate for most adults:
- Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
- Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
The TDEE calculator does this for you in metric or imperial units.
Step 2: choose a deficit
A pound of body fat stores roughly 3,500 calories, so a daily deficit of about 500 calories leads to about 1 lb of loss a week, and 250 calories to about 0.5 lb. Slower is easier to sustain and helps you keep muscle.
Worked examples
| Person | Maintenance (TDEE) | Lose 0.5 lb/week | Lose 1 lb/week |
|---|---|---|---|
| Woman, 35, 5'5", 165 lb, lightly active | 1,986 | 1,736 | 1,486 |
| Man, 40, 5'10", 200 lb, moderately active | 2,826 | 2,576 | 2,326 |
| Woman, 55, 5'3", 150 lb, sedentary | 1,494 | 1,244 | 994 * |
* At this pace, the target falls close to or below a recommended minimum, so a slower rate is the safer choice.
Notice how much smaller, older and less active people have to cut: the same 1 lb a week takes a bigger share of a smaller budget. That's why a slower rate often makes more sense for them.
Step 3: set your macros
Within your calorie target, prioritize protein to protect muscle, then split the rest between carbs and fat to suit your preferences. The calorie and macro calculator turns your target into daily grams and per-meal amounts.
Tips that make a deficit easier
- Eat protein and fiber at every meal. Both keep you fuller for longer.
- Watch liquid calories such as soda, juice, alcohol and specialty coffees.
- Lift weights two or three times a week to keep muscle while you lose fat.
- Sleep well. Short sleep increases hunger. The sleep calculator helps you plan a bedtime.
- Recalculate as you go, because maintenance calories fall as you lose weight.
To see where you stand, check your BMI and read what a healthy BMI is, and its limits.
This guide is for general information and isn't medical advice. Talk to a doctor before starting a diet, especially if you're pregnant, have a medical condition or take medication.