TheFreeTool

Calorie Calculator

Enter a few details about yourself and get an estimate of the calories your body burns at rest, and how many you need each day to keep your weight, lose it slowly or gain it slowly.

Good to know

This tool gives general information only and is not medical or dietary advice. Speak to a doctor or registered dietitian before changing your diet, especially if you have a health condition.

What it does

  • Basal metabolic rate (BMR) using the Mifflin-St Jeor equation
  • Five activity levels, from desk job to very hard training
  • Maintenance, slow weight loss and slow weight gain targets
  • Metric or imperial units

How to use it

  1. Choose your sex and enter your age.
  2. Choose metric or imperial, then enter height and weight.
  3. Pick your activity level and read your daily calories.

How are daily calories estimated?

Your BMR is the energy your body uses at rest. The Mifflin-St Jeor equation estimates it from your weight, height, age and sex. Multiplying it by an activity factor, from 1.2 for little exercise to 1.9 for very hard training, gives the calories you burn in a day.

Eating about that amount keeps your weight steady. About 500 calories a day less leads to a slow loss of roughly half a kilo or one pound a week, and 500 more leads to a slow gain. These are estimates, because bodies differ.

Example

A 30-year-old man, 175 cm and 70 kg, with light activity has a BMR of about 1,649 calories and needs about 2,267 a day to keep his weight. About 1,767 would give a slow loss, and about 2,767 a slow gain.

Questions people ask

How accurate is it?
It is an estimate. Real needs vary with muscle, genetics, health and daily movement. Track your weight over a few weeks and adjust.
Is it safe to eat much less?
Very low calorie diets can be harmful. This tool never suggests going below your BMR. Talk to a doctor before a big change.
Does it work for teenagers or pregnancy?
No. It is for adults from 15 to 100. Teenagers growing, and pregnant or breastfeeding women, have different needs.

Disclaimer

This tool is for general information only and is not medical advice. Results are estimates and do not diagnose, treat or replace a doctor, dietitian or other health professional. Talk to a qualified professional before you change your diet, exercise or health routine. You use this tool at your own risk, and TheFreeTool is not liable for any loss or harm that follows. Read the full disclaimer

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