# Calorie calculator

Estimate how many calories you need each day

Use it at https://www.quicktoolz.com/tools/calorie-calculator. From QuickToolz.

Your daily calorie need is your basal metabolic rate multiplied by an activity factor. A woman with a BMR of 1,320 kcal who exercises lightly needs about 1,815 kcal a day to stay at the same weight. Eating about 500 fewer a day is a common way to lose weight slowly.

## How it works

daily calories = BMR × activity factor

We work out your BMR with the Mifflin-St Jeor equation, then multiply it by a standard factor for your activity.

We never suggest going below 1,200 kcal a day for women or 1,500 for men without medical advice.

Worked example: A BMR of 1,320 kcal with light exercise is 1,320.25 × 1.375 ≈ 1,815 kcal a day.

## Examples

| Activity | Factor | Example daily calories |
| --- | --- | --- |
| Little or no exercise | 1.2 | 1,584 kcal |
| Light exercise, 1 to 3 days a week | 1.375 | 1,815 kcal |
| Moderate exercise, 3 to 5 days a week | 1.55 | 2,046 kcal |
| Hard exercise, 6 to 7 days a week | 1.725 | 2,277 kcal |
| Very hard exercise or physical job | 1.9 | 2,508 kcal |

## What this tool doesn't cover

- This is an estimate for adults, and not medical advice.
- It isn’t for use during pregnancy, or with an eating disorder. Please talk to a doctor.

## Questions

### How many calories should I cut to lose weight?

A common guide is about 500 kcal a day. Talk to a doctor before a big change.

### Which activity level should I choose?

Most people overestimate. If you’re unsure, choose the lower one.

### Why is there a minimum?

Eating too little can be harmful, so we stop at a safe floor.

### How do I work out my daily calories?

Start with your BMR, then multiply it by your activity level. The result estimates how much keeps your weight steady.

### Does this replace advice from a dietitian?

No. It gives a general estimate for healthy adults. Speak to a doctor or dietitian if you are pregnant, have a health condition, or plan a big change.

## Sources

- [Mifflin et al. (1990), American Journal of Clinical Nutrition](https://doi.org/10.1093/ajcn/51.2.241)