TDEE Calculator

What this calculator does

This calculator estimates your Total Daily Energy Expenditure (TDEE)—how many calories you burn per day including activity—and, if you choose a goal, a target calorie intake and optional zigzag schedule. It also shows BMR, macros (protein, carbs, fat), and when relevant a simple zigzag (e.g. 3 higher-calorie days, 4 lower-calorie days per week).

Units: calories per day for all energy values; macros in grams. Typical users include people aiming to maintain, lose, or gain weight and anyone setting daily calorie targets. It is an estimate only; metabolism and adherence vary.

How to use it

1. Enter Unit (metric or imperial), weight, height, age, sex, and activity level.
2. Pick a BMR formula (Mifflin-St Jeor, Harris-Benedict, or Katch-McArdle); for Katch-McArdle add body fat %.
3. Set Goal: Maintain, Lose, or Gain. For Lose/Gain, set rate (lb/week) (e.g. 0.5 or 1).
4. Read maintenance TDEE, target calories, and if applicable zigzag split and suggested macros in the Result panel.

All inputs are in the "Inputs" section; the result updates as you change values. Target is capped at a safe minimum (e.g. 1,200 kcal/day) for safety.

Formulas used

TDEE = BMR × activity multiplier. BMR is computed with the formula you chose (see the BMR calculator for equation details). Activity multipliers used here:

• Sedentary: 1.2
• Light: 1.375
• Moderate: 1.55
• Active: 1.725
• Very active: 1.9

Target calories:

• Maintain: target = TDEE.
• Lose: target = TDEE − (rate_lb_per_week × 500/7) kcal/day (≈500 kcal per lb per week).
• Gain: target = TDEE + (rate_lb_per_week × 500/7) kcal/day.

Target is floored at a minimum (e.g. 1,200 kcal/day) for safety.

Zigzag: For lose/gain, a simple zigzag splits the week into 3 higher-calorie days and 4 lower-calorie days so the weekly total matches your target (7 × target calories), with a fixed difference between high and low days (e.g. 400 kcal). This can help with adherence (e.g. higher calories on training days).

Macros: Protein from body weight (e.g. 2.2 g per kg), fat at ~25% of target calories, remainder as carbs. Use as a starting point; individual needs vary.

Interpretation & examples

• Maintenance (TDEE) is your estimated daily burn; eating this on average keeps weight stable.
• Target is the intake to aim for given your goal and rate. Loss/gain in real life depends on consistency and accuracy of intake.
• Zigzag can help with adherence (e.g. higher calories on training days, lower on rest days).
• Example 1: TDEE 2,400 kcal, goal "lose," 0.5 lb/week → target ≈ 2,165 kcal/day; zigzag might show 3 days at ~2,365 and 4 days at ~1,965.
• Example 2: TDEE 1,800 kcal, goal "maintain" → target = 1,800 kcal/day.
• Example 3: TDEE 2,600 kcal, goal "gain," 0.5 lb/week → target ≈ 2,636 kcal/day.

History & background

TDEE concepts come from energy balance research; activity multipliers are based on population studies (e.g. FAO/WHO and sports science). The 3,500 kcal ≈ 1 lb rule is a long-standing heuristic; individual loss/gain varies. Zigzag and macro splits are common in fitness and diet coaching; this calculator provides a simple, consistent starting point.

Limitations & safety notes

• Estimates only, not medical or dietary advice. Metabolism and adherence vary.
• Very low calorie intakes can be harmful. Stay within a safe minimum (e.g. 1,200+ kcal unless under supervision). The calculator floors target at a minimum for this reason.
• For medical conditions, pregnancy, or eating disorders, consult a doctor or dietitian. Do not use as the sole basis for extreme restriction or rapid weight change.