TDEE calculator
Your TDEE is the total number of calories you burn in a day. It is your resting metabolism (BMR) multiplied by an activity factor. It is the single most useful number for fat loss or muscle gain, because it is the line your intake sits above or below.
Used only for the equation constants.
Daily calories
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Protein a day
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BMR
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Maintenance (TDEE)
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We won't show a target that low.
Your goal maths lands below a level we consider safe to recommend, so we're showing the floor instead. Very low intakes are hard to sustain and can do more harm than good. If losing weight matters to you, a smaller deficit you can actually keep beats a large one you can't. If food or eating feels distressing, please talk to someone — there are support links in the footer.
Why these numbers?
Calories use the Mifflin-St Jeor equation for BMR, which a 2005 review of four common equations found the most reliable, though any equation can be off for one person. It is multiplied by a common activity factor (not an official standard) for maintenance (TDEE). Fat loss shows maintenance minus 20%, which is our rule; guidelines more often suggest a deficit of 500 to 750 calories a day. Building muscle adds 10%, also our rule.
Protein: losing fat or building muscle assumes you exercise, so it shows 1.4–2.0 g per kg of body weight, the range sports-nutrition research gives for most people who exercise. "Maintain" shows 0.8 g per kg, the recommended minimum for adults. From 65, it shows at least 1.0–1.2 g per kg (1.2 or more if you are active), the range set out for older adults. The big number is the middle of the range.
These are population estimates, not a prescription. Your real needs vary. See our editorial policy for how we source this.
Pair this with the fasting calculator and the BMR calculator.
How to use the TDEE calculator
Choose your units first: metric, US (pounds, feet and inches) or UK (stone, feet and inches). Then enter your sex at birth, age, weight and height. Pick the activity level that matches a typical week and the number of meals in your eating window. Then choose a goal: lose fat, maintain or build muscle.
The results show daily calories for your goal, protein a day, your BMR and your maintenance (TDEE). Under them, the calculator splits calories and protein across your meals.
How the TDEE maths works
The calculator works out BMR with the Mifflin-St Jeor equation. Take 10 × your weight in kg, add 6.25 × your height in cm and subtract 5 × your age. Then add 5 for a man or subtract 161 for a woman. A 2005 review of four common equations found Mifflin-St Jeor the most reliable, landing within 10% of measured values for more people than the others. Any equation can still be wrong for one person.
BMR is then multiplied by an activity factor. The last column uses the woman in the worked example below.
| Activity level in the calculator | Multiplier | Her maintenance |
|---|---|---|
| Sedentary: little or no exercise | 1.2 | 1,674 kcal |
| Light: exercise 1 to 3 days a week | 1.375 | 1,918 kcal |
| Moderate: exercise 3 to 5 days a week | 1.55 | 2,163 kcal |
| Very active: hard exercise 6 to 7 days a week | 1.725 | 2,407 kcal |
| Extra active: physical job or training twice a day | 1.9 | 2,651 kcal |
These multipliers appear in many calculators, but no official body sets them. The FAO/WHO/UNU report on human energy needs puts sedentary or lightly active lifestyles at 1.40 to 1.69 times BMR. By that measure, the 1.2 setting is on the low side.
The goal then adjusts maintenance. “Lose fat” takes off 20%, which is our rule. Obesity guidelines usually set a daily deficit of 500 or 750 calories instead. “Build muscle” adds 10%, also our rule, and “Maintain” leaves TDEE as it is.
How many calories for intermittent fasting? A worked example
The calculator opens with these values: a woman aged 35, 165 cm (5 ft 5 in) and 70 kg (154 lb). She is moderately active and wants to lose fat over 2 meals.
- BMR: 700 + 1,031 − 175 − 161 = 1,395 kcal.
- Maintenance: 1,395 × 1.55 = 2,163 kcal.
- Fat-loss target: 2,163 × 0.8 = 1,730 kcal, a deficit of 433 kcal a day.
- Protein: 1.4 to 2.0 g × 70 kg = 98 to 140 g, shown as 119 g.
- Per meal: about 865 kcal and 60 g of protein.
Her 20% cut is smaller than a 500-calorie deficit, which would put her at 1,663 kcal. That holds for anyone whose maintenance is under 2,500 kcal. Above that, our rule takes off more than 500.
Your fasting schedule decides when you eat these calories, and the target decides how much. A trial followed 139 adults with obesity for 12 months. Those who ate within 8 hours on a calorie target lost 8.0 kg. Those on the same target with no time limit lost 6.3 kg. That difference was too small to rule out chance.
The calorie floor
The calculator never shows a target below 1,200 kcal a day for women or 1,500 kcal for men. Take a woman of 60, 155 cm and 50 kg who is sedentary. Her BMR is 1,008 kcal and her maintenance 1,209 kcal, so a 20% cut would be 967 kcal. The calculator shows 1,200 and a note instead. The floors are the bottom of the usual targets in the 2013 AHA/ACC/TOS obesity guideline.
Protein ranges by goal and age
“Lose fat” and “Build muscle” assume you exercise and show 1.4 to 2.0 g per kg. “Maintain” shows the adult minimum of 0.8 g per kg. From 65, every goal shows 1.0 to 1.2 g per kg. If you choose 1 meal, the calculator points out that the whole day’s food is a lot to eat in one sitting.
What the result means, and who should take care
Your TDEE is an estimate for an average person with your figures. Eat at the target for two or three weeks and compare your weekly average weight with where you started. If the trend doesn’t match your goal, change the activity level or the target a little and watch for another two weeks.
Skip the fat-loss target if you are under 18, pregnant or underweight, or if you have a history of an eating disorder. If you take insulin or a sulfonylurea for diabetes, talk to your doctor before cutting calories or fasting.
Related tools and guides
The fasting calculator gives the start and end times of your eating window. Our guide explains how a deficit fits a fasting plan. The 7-day plan shows how to fill two meals at your target. When your weight stalls, the stalled-scale checklist helps you find the cause.
Frequently asked
How many calories should I eat when intermittent fasting?
Intermittent fasting does not change how many calories your body needs. Eat the fat-loss or maintenance figure from the TDEE calculator inside your eating window. In a trial that matched calories, people eating within 8 hours lost about the same weight as people cutting calories alone. The daily total is the number to get right.
What is the difference between TDEE and BMR?
BMR is the energy your body uses at complete rest. TDEE is BMR multiplied by an activity factor, so it also covers walking, work and exercise. Your calorie targets come from TDEE, and the BMR calculator explains the resting figure on its own.
Why does the calculator show 1,200 calories when my maths comes out lower?
The calculator will not display a fat-loss target under 1,200 kcal a day for a woman or 1,500 kcal for a man. When 20% below your maintenance lands lower, it shows that floor with a note. Both figures are the bottom of the usual targets that a 2013 US obesity guideline gives, not official minimums.
How much protein should I eat while intermittent fasting?
Adults need at least 0.8 g of protein per kg of body weight a day. If you exercise, the advised range is 1.4 to 2.0 g per kg. Adults from 65 need at least 1.0 to 1.2 g per kg. The calculator shows the range for your goal and age, with the middle of it as the main figure.
Which activity level should I choose?
Pick the level that matches a normal week, not your busiest one. Someone who sits at a desk and trains two or three times a week fits Light or Moderate better than Very active. If your weight holds steady for a few weeks at the maintenance figure, the level you chose is about right.