# Calorie Calculator

> Estimate the calories you need each day to keep your weight steady or to lose or gain at a set weekly rate, using Mifflin–St Jeor and your activity level.

Category: Health & fitness · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/calorie-calculator

Your maintenance calories are your resting energy needs (Mifflin–St Jeor) multiplied by an activity factor. A weekly weight-change goal then adds or removes a fixed number of calories a day.

Also called: Daily calorie calculator, Calorie intake calculator.

## Inputs
- Sex (options: Female, Male; default female)
- Age (unit years; default 30)
- Units (options: Metric (cm, kg), US (ft, in, lb); default metric)
- Height (unit cm; default 165)
- Weight (unit kg; default 60)
- Height (feet) (unit ft; default 5)
- Height (inches) (unit in; default 5; optional)
- Weight (unit lb; default 132)
- Activity level (options: Sedentary (little or no exercise), Lightly active (1–3 days a week), Moderately active (3–5 days a week), Very active (6–7 days a week), Extremely active (physical job or twice-daily training); default moderate)
- Goal (options: Maintain weight, Lose 0.25 kg (≈0.5 lb) a week, Lose 0.5 kg (≈1 lb) a week, Lose 1 kg (≈2 lb) a week, Gain 0.25 kg (≈0.5 lb) a week, Gain 0.5 kg (≈1 lb) a week; default maintain)

## Results
- Calories per day for your goal
- Maintenance calories (TDEE)
- Resting energy (BMR)
- Daily adjustment for the goal

## Formula

```
BMR = 10W + 6.25H − 5A + s;  Maintenance = BMR × activity factor;  Target = Maintenance + (weekly change in kg × 7,700 ÷ 7)
```

Where:
- W: weight in kg
- H: height in cm
- A: age in years
- s: +5 for men, −161 for women
- activity factor: 1.2 (sedentary) to 1.9 (extremely active)
- 7,700: approximate kcal in 1 kg of body-weight change

## Worked example
1. BMR = 10 × 60 + 6.25 × 165 − 5 × 30 − 161 = 600 + 1,031.25 − 150 − 161 = 1,320.25 kcal.
2. Maintenance = 1,320.25 × 1.55 (moderately active) = 2,046 kcal a day.
3. Losing 0.5 kg a week needs about 0.5 × 7,700 ÷ 7 = 550 kcal a day less.
4. Target = 2,046 − 550 ≈ 1,496 kcal a day.

**Result:** A moderately active 30-year-old woman, 165 cm and 60 kg, needs about 2,046 kcal a day to maintain her weight, or about 1,496 kcal to lose roughly 0.5 kg a week.

## What the result means

Treat the number as a starting point. Track your weight for two to four weeks; if it moves faster or slower than planned, adjust intake by 100–200 kcal a day. Weight loss usually slows over time as the body adapts, so the same deficit produces less loss later on.

## Assumptions and limits
- Mifflin–St Jeor equation for resting energy expenditure in healthy adults.
- Conventional activity multipliers: 1.2, 1.375, 1.55, 1.725 and 1.9.
- About 7,700 kcal per kg of body-weight change (the metric form of the “3,500 kcal per pound” rule).
- Individual energy needs can differ noticeably from any prediction equation.
- The 7,700 kcal rule ignores metabolic adaptation, so it overstates long-term weight loss (Hall, 2008).
- Not for children, pregnancy or breastfeeding, or people with medical conditions that affect metabolism.

## Questions

### What is the difference between this and the BMR calculator?

The BMR calculator gives resting energy and a table by activity level. This page adds a weight goal and shows the daily calories needed to reach it.

### Is it safe to lose 1 kg a week?

For many people it means a deficit of about 1,100 kcal a day, which is hard to sustain and can leave intake below resting needs. A slower rate is easier to keep up; talk to a doctor or dietitian before a large deficit.

### Why has my weight loss slowed on the same calories?

As you lose weight your energy needs fall, and the body adapts. Recalculate with your new weight every few kilograms.

## Sources
- [Mifflin MD et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr, 1990](https://www.qxmd.com/r/2305711)
- [Hall KD. What is the required energy deficit per unit weight loss? Int J Obes, 2008](https://pmc.ncbi.nlm.nih.gov/articles/PMC2376744)

## Related calculators
- [BMR Calculator](https://calculators.geekmidst.com/calculators/bmr-calculator)
- [BMI Calculator](https://calculators.geekmidst.com/calculators/bmi-calculator)
- [Macro Calculator](https://calculators.geekmidst.com/calculators/macro-calculator)
- [Calories Burned Calculator](https://calculators.geekmidst.com/calculators/calories-burned-calculator)
- [TDEE Calculator](https://calculators.geekmidst.com/calculators/tdee-calculator)
- [Calorie Deficit Calculator](https://calculators.geekmidst.com/calculators/calorie-deficit-calculator)

_This is a general screening estimate for adults, not medical advice or a diagnosis. Talk to a qualified health professional about your health._

Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/calorie-calculator