Tools

Calorie calculator: how many calories should I eat a day?

How many calories does your body use in a day? This works it out from your age, height, weight and how active you are.

Written by Poshan Labs. Sources are named on the page. Last updated 26 October 2026.

Your answer will show here when the boxes are filled in correctly.

Height
ftin

Not for pregnancy, breastfeeding, under-18s or anyone with an eating disorder. If you take insulin or sugar-lowering tablets, eating less can drop your sugar too low; ask your doctor first.

The first call is free

Tell Puja what's going on and she will tell you honestly whether she can help.

How many calories do I need a day?

It depends on your age, height, weight and how active you are. This calculator:

  • finds your energy at rest with the Mifflin-St Jeor equation
  • then multiplies it by an activity factor, from 1.2 if you mostly sit to 1.725 if you are very active

Treat the answer as a starting point, because every body is a little different.

How this works

It uses the Mifflin-St Jeor equation, the most reliable of the common formulas: 10 × weight (kg) + 6.25 × height (cm) − 5 × age, plus 5 for men or minus 161 for women. That's your energy at rest. It's then multiplied by an activity factor: 1.2 mostly sitting, 1.375 light, 1.55 moderate, 1.725 very active. Every body is a little different, so treat the answer as a starting point.

A number is a starting point, not a plan. On a free call, Puja looks at it with your reports and your routine.

Questions about your answer?

Once you have an answer, it goes into the message for you, so there is nothing to copy.