---
title: "Calorie Calculator"
description: "Work out how many calories to eat per day to lose, maintain, or gain weight. Uses the Mifflin-St Jeor equation, no signup required, no upload required."
url: https://findutils.com/calculate/calorie-calculator/
category: calculate
---

# Calorie Calculator

Work out how many calories to eat per day to lose, maintain, or gain weight. Uses the Mifflin-St Jeor equation, no signup required, no upload required.

**Use this tool:** [Calorie Calculator](https://findutils.com/calculate/calorie-calculator/)

## Programmatic access

- REST id `calorie-calculator`: POST https://api.findutils.com/api/tools/calorie-calculator/execute (reference: https://findutils.com/api/calorie-calculator/)
- MCP tool `calorie_calculator` on https://mcp.findutils.com (reference: https://findutils.com/mcp/calorie-calculator/)

## Why use this calorie calculator?

Your daily calorie target is your maintenance level plus or minus a deliberate amount. This tool works out maintenance from the Mifflin-St Jeor equation and your activity level, then applies the deficit or surplus you choose, so you can see the target and the arithmetic behind it at the same time. It runs entirely in your browser.

## Frequently Asked Questions

### How is my calorie target calculated?

Your basal metabolic rate comes from the Mifflin-St Jeor equation, which uses your sex, age, weight, and height. That is multiplied by an activity factor (1.2 for sedentary up to 2.1 for extra active) to give maintenance calories, and then the rate you pick adds or subtracts 250, 500, or 1000 calories a day.

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

They share the same equations. The TDEE calculator leads with your total daily energy expenditure and shows the full breakdown; this one leads with the single number to eat and the deficit that produces it. Both return the same figures for the same inputs.

### How fast will I lose weight?

A 500 calorie daily deficit is roughly 0.45 kg (about 1 lb) a week, using the standard planning figure of 7,700 calories per kilogram of body mass. Real results vary with water balance, training, and adherence.

### Is a 1000 calorie deficit safe?

It is aggressive, and for many people it drops intake below what is sensible. Treat the mild and moderate rates as the default and speak to a healthcare professional before running a large deficit for any length of time.

### Is my data uploaded anywhere?

No. The calculation runs in your browser and nothing you type is sent to a server or saved between sessions.

### Do I need an account?

No. FindUtils Calorie Calculator requires no signup, no usage limits, and no watermarks.

## Related Tools

- [TDEE Calculator](https://findutils.com/calculate/tdee-calculator/)
- [Macro Calculator](https://findutils.com/calculate/macro-calculator/)
- [BMI Calculator](https://findutils.com/calculate/bmi-calculator/)
- [Body Fat Calculator](https://findutils.com/calculate/body-fat-calculator/)
- [Water Intake Calculator](https://findutils.com/calculate/water-intake-calculator/)
- [One Rep Max Calculator](https://findutils.com/calculate/one-rep-max-calculator/)