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Calorie and TDEE Calculator Calculators

Daily calorie needs from your BMR and activity level.

Calorie and TDEE Calculator is a free online tool that daily calorie needs from your BMR and activity level. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.

Price
Free — no account, no quota, no watermark
Category
Calculators
Where it runs
In your browser, on your device
Files uploaded
None
Technology
plain JavaScript
Settings
6
Works offline
Yes, after the first visit

About Calorie and TDEE Calculator

This uses Mifflin–St Jeor, which has held up best of the common BMR equations in validation studies — typically within 10% for most people. Activity multipliers are the standard Harris–Benedict set and are the weakest link: most people overestimate their activity level by roughly one step.

How to use it

  1. Enter units, sex at birth and age.
  2. Adjust the remaining 3 settings if the defaults do not fit your case.

The 6 settings

SettingWhat it doesDefault
UnitsChoose from 2: Metric (kg, cm), Imperial (lb, in).Metric (kg, cm)
Sex at birthChoose from 2: Female, Male.Female
AgeRange 1–120.30
WeightA numeric value.70
HeightA numeric value.170
Activity levelChoose from 5: Sedentary — desk job, no exercise, Light — exercise 1–3 days/week, Moderate — exercise 3–5 days/week, Active — exercise 6–7 days/week, Very active — physical job or twice daily.Moderate — exercise 3–5 days/week

Under the hood

Runs onplain JavaScript — runs the whole thing
ControlsUnits, Sex at birth, Age, Weight, Height, Activity level

Questions

Why is my real intake different from this number?

Because the equation cannot see your body composition, thyroid function, NEAT or how accurately you log food. Use the figure as a starting point, track weight for two weeks, and adjust by what actually happens.

How fast should I lose weight?

A 500 kcal daily deficit is roughly 0.5 kg a week, which is sustainable for most people. Larger deficits cost muscle and adherence. This is general information, not medical advice.

What does the activity level option change?

It offers 5 choices — Sedentary — desk job, no exercise, Light — exercise 1–3 days/week, Moderate — exercise 3–5 days/week and Active — exercise 6–7 days/week and more. The default is Moderate — exercise 3–5 days/week, which suits most cases; change it when your input or your destination calls for something specific.

What are the limits on age?

It accepts 1 to 120, starting at 30.

Is the arithmetic exact?

It uses double-precision floating point — about 15 significant figures, far more than the inputs justify. Displayed rounding is cosmetic; the underlying numbers are not rounded between steps, so chained results do not drift.