# TDEE Calculator

## Overview
A tool to calculate Total Daily Energy Expenditure (TDEE) and Basal Metabolic Rate (BMR) with calorie targets and macronutrient breakdowns.

## Features
- Calculate BMR using Mifflin-St Jeor (default) or Harris-Benedict formula
- Calculate TDEE based on five activity levels
- Generate calorie targets for weight loss (-500), maintenance, and weight gain (+500)
- Calculate macronutrient split (protein, carbs, fat) for each calorie goal
- Support metric (kg/cm) and US customary (lbs/ft+in) unit systems
- Export results to PDF

## Inputs
- Gender (Male/Female)
- Age (15-120 years)
- Height (cm or ft+in)
- Weight (kg or lbs)
- Activity Level (Sedentary, Light, Moderate, Very Active, Extremely Active)
- Formula (Mifflin-St Jeor or Harris-Benedict)

## Outputs
- BMR: Basal Metabolic Rate (calories burned at rest)
- TDEE: Total Daily Energy Expenditure (calories burned with activity)
- Calorie Goals: Weight Loss, Maintenance, Weight Gain targets
- Macronutrient Breakdown: Protein, Carbs, Fat grams per goal

## Formulas
- Mifflin-St Jeor Male: 10W + 6.25H - 5A + 5
- Mifflin-St Jeor Female: 10W + 6.25H - 5A - 161
- Harris-Benedict Male: 88.362 + 13.397W + 4.799H - 5.677A
- Harris-Benedict Female: 447.593 + 9.247W + 3.098H - 4.330A
- TDEE = BMR * Activity Multiplier

## Use Cases
- Fitness planning and nutrition tracking
- Weight loss or gain goal setting
- Calorie deficit/surplus calculation
- Macronutrient planning for diet