Toolkit Shelf

Health Calculators

Calorie Calculator

Use this calorie calculator to estimate maintenance calories, BMR, and simple daily targets for gradual weight loss or gain.

Reviewed May 25, 2026EstimateFormula shown

Live calculator

Calorie calculator

Maintenance calories2,008 / day

Estimated calories to maintain current weight.

Weight loss target1,708 / day

A moderate estimate using about 300 calories below maintenance.

BMR1,460 / day

Basal metabolic rate estimate before activity adjustment.

Formula

Calorie estimate formula

Maintenance calories = Mifflin-St Jeor BMR x activity multiplier

This is a planning estimate. Actual needs vary by body composition, health, and activity.

How to use

Steps

  1. Choose sex, age, height, and weight.
  2. Select the closest activity level.
  3. Read estimated maintenance calories.
  4. Use loss and gain targets as moderate planning estimates.

Example

Sample calculation

Profile35-year-old female
Height and weight5 ft 6 in, 165 lb
ActivityLight activity
Maintenance2,017 calories/day

Calculator use

Best for

  • Quick maintenance calories from sex, age and weight.
  • Wellness, nutrition, pregnancy, or fitness planning when a rough estimate is enough.
  • Scenario comparisons before changing calorie, macro, or body-measurement assumptions.
  • Planning alongside professional medical or nutrition advice, not as a diagnosis.

Before relying on it

Check first

  • Entering sex, age and weight from different time periods or scenarios.
  • Treating a calculator result as medical advice or a diagnosis.
  • Using stale body, activity, pregnancy, or nutrition inputs when your situation has changed.
  • Ignoring context such as age, medication, training status, medical history, or professional guidance.

Benchmarks

How to read the result

The calculator is a decision aid, not a fixed rule. Use the output to compare scenarios and document your assumptions.

-300/dayModerate deficit

Often used as a gentler weight-loss planning target.

MaintenanceStable weight

Estimated calories to maintain current weight.

+300/dayModerate surplus

Often used for gradual weight gain planning.

Calculator accuracy

Methodology and assumptions

The formula, inputs, example, and limitations are shown so the result is checkable, not just a number in a box.

Formula

Maintenance calories = Mifflin-St Jeor BMR x activity multiplier

Inputs used

Sex, Age, Weight, Height, Activity level

Limitations

Results are estimates for quick planning and should be checked before important financial, legal, tax, health, or business decisions.

Last reviewed

May 25, 2026

Cite this page

Toolkit Shelf. Calorie Calculator. Retrieved May 25, 2026, from https://toolkitshelf.com/tools/calorie-calculator

FAQ

Common questions

How are maintenance calories calculated?

The calculator estimates BMR with the Mifflin-St Jeor formula, then multiplies by an activity factor.

Are calorie calculators exact?

No. They are estimates. Track real-world weight and energy changes to adjust over time.

Should I use this for medical nutrition advice?

No. Talk with a qualified professional for medical, eating disorder, pregnancy, or disease-specific nutrition guidance.