Health & FitnessFormula-based · Runs in your browser

Calorie Needs Calculator

Estimate daily maintenance calories and apply an optional daily adjustment.

Preparing saved example…

Inputs

Enter the values you know. Optional fields may be left empty.

Local save controls below
Required
Required
Required
kg
Required
cm
Required
Optional; negative or positive
kcal

Result

Updates as valid inputs change.

Calculated locally
Adult estimate only. Do not use this tool as medical or eating-disorder treatment advice.
Estimated maintenance
Adjusted daily target
Estimated BMR
Weekly energy adjustment

Saved locally, explained clearly

Drafts, calculations, scenarios, and workflow progress stay in this browser unless you export them.

Opening local database…

Calculation steps

Follow what happened from the selected formula to the displayed answer.

Show substituted values and intermediate working
Calculate current inputs to see the working.
  1. 1

    Formula selected

    The calculator uses the following formula or method.

    Maintenance calories = Mifflin–St Jeor BMR × activity factor

  2. 2

    Values entered

    Your values are placed into the calculation.

    Enter values to see what is used in this step.

  3. 3

    Result calculated

    The formula or method produces the following result values.

    Results will appear after a successful calculation.

  4. 4

    Answer formatted

    Displayed values are rounded and formatted using each output’s configured precision.

Scenario comparison

Save working scenarios, then select two or three to compare. Formula versions and inputs remain visible.

No scenarios saved for this calculator yet.

Recent calculations

Successful calculations are retained locally according to your privacy settings.

No local history for this calculator yet.

Data and privacy

How it works

The calculator estimates BMR, then multiplies it by the selected activity factor. The optional adjustment is added afterward.

Input query strings and outputs

Use an input name in this page’s URL as ?name=value, and join additional inputs with &. Portable shared links may instead use the compact ?ac= state parameter.

Input query strings

6
  • ?sex= Equation sex constant

    Choice · Required · Default: female · Accepted values: female, male

  • ?age= Age

    Number · Required · Default: 35

  • ?weightKg= Weight

    Number · Required · Default: 70

  • ?heightCm= Height

    Number · Required · Default: 170

  • ?activityFactor= Activity factor

    Choice · Required · Default: 1.375 · Accepted values: 1.2, 1.375, 1.55, 1.725, 1.9

  • ?dailyAdjustment= Daily calorie adjustment

    Number · Optional · Default: 0

Outputs

4
  • maintenanceCalories Estimated maintenance

    Whole number · Primary output · Suffix: kcal/day

  • targetCalories Adjusted daily target

    Whole number · Suffix: kcal/day

  • bmr Estimated BMR

    Whole number · Suffix: kcal/day

  • weeklyEnergyDifference Weekly energy adjustment

    Whole number · Suffix: kcal/week

Limits

Needs vary with health, body composition, pregnancy, medications, training, and measured activity.

Sources
Limitations
  • Adult estimate only. Do not use this tool as medical or eating-disorder treatment advice.
  • Health results are educational estimates, not a diagnosis or treatment recommendation. Individual circumstances may require a qualified clinician's assessment.