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Free Calorie & Macro Calculator (TDEE)

A free calorie and macro calculator estimates your daily calorie needs using the Mifflin-St Jeor BMR equation and an activity multiplier to find your TDEE. Enter your age, gender, weight, height, and activity level to get maintain, lose, and gain calorie targets, each with a protein, carbs, and fat breakdown in grams you can fine-tune with sliders — works in metric or imperial, no signup, runs in your browser.

Find out how many calories you need each day and how to split them across protein, carbs, and fat. The tool calculates your Basal Metabolic Rate (BMR) with the Mifflin-St Jeor equation — the most accurate everyday formula — then multiplies it by an activity factor (sedentary to extra active) to estimate your Total Daily Energy Expenditure (TDEE), the calories needed to maintain your current weight. From there you get three goal-based targets: maintain, lose weight (a ~500 cal/day deficit), and gain weight (a ~500 cal/day surplus). Each goal shows a recommended macronutrient breakdown in grams using a default 30% protein / 40% carbs / 30% fat split that you can adjust with sliders. Switch between metric (kg/cm) and imperial (lbs/inches) units. All math runs locally in your browser — free, no signup, nothing uploaded.

Gender
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Estimates use the Mifflin-St Jeor equation and standard activity multipliers. The ~500 cal deficit and surplus target roughly 0.45 kg (1 lb) of weight change per week. These figures are for general guidance only and are not a substitute for advice from a doctor or registered dietitian.

Runs 100% in your browser. Your data never leaves your device.

Implements the Mifflin-St Jeor BMR equation and standard activity multipliers in plain JavaScript. BMR is multiplied by your activity factor to get TDEE, then a ±500 calorie offset produces the lose and gain targets. Macros are derived from your chosen percentage split using 4 cal/g for protein and carbs and 9 cal/g for fat. All calculations run locally in your browser with no external libraries or server calls.

How to Use Calorie & Macro Calculator (TDEE)

  1. Select your gender and choose metric (kg/cm) or imperial (lbs/inches) units
  2. Enter your age, weight, and height, then pick your activity level from the dropdown
  3. Click Calculate to see your BMR and TDEE (maintenance calories)
  4. Review the maintain, lose, and gain calorie targets, each with a protein, carbs, and fat breakdown
  5. Adjust the macro sliders to match your preferred protein, carbs, and fat ratio

When Would You Use This?

Anyone starting a cut or bulk uses this to turn a vague goal into a concrete daily calorie and protein target instead of guessing. The TDEE number is the anchor — eat at it to maintain, ~500 below to lose about a pound a week, ~500 above to gain.

Lifters and people tracking macros in an app like the gram targets for protein, carbs, and fat rather than just a calorie ceiling. The adjustable sliders let you favor higher protein on a cut or more carbs around training without recalculating by hand.

Keep in mind these are estimates. The Mifflin-St Jeor equation and activity multipliers give a solid starting point, but real energy expenditure varies — track your weight for two to three weeks and adjust calories up or down based on what actually happens on the scale.

Frequently Asked Questions

Is this calorie and macro calculator free to use?
Yes, completely free. No signup, no login, no payment ever.
Do I need to create an account?
No account needed. Open the tool, enter your details, and calculate immediately.
Is my data safe?
Everything runs in your browser. Your age, weight, and height are never uploaded to our servers.
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the calories your body burns at complete rest just to stay alive. TDEE (Total Daily Energy Expenditure) is BMR multiplied by an activity factor — it estimates the total calories you burn in a day including movement and exercise, which is the number you eat at to maintain your weight.
Which formula does it use?
It uses the Mifflin-St Jeor equation, widely regarded as the most accurate everyday BMR formula. For men: BMR = 10 × kg + 6.25 × cm − 5 × age + 5. For women: BMR = 10 × kg + 6.25 × cm − 5 × age − 161.
Why is the deficit and surplus 500 calories?
A daily change of about 500 calories adds up to roughly 3,500 per week, which corresponds to about 0.45 kg (1 lb) of weight change. It is a common, sustainable starting point — you can eat below or above these targets, but larger changes are harder to maintain.
How should I split my macros?
The tool defaults to 30% protein, 40% carbs, and 30% fat, a balanced starting point. You can move the sliders to favor higher protein when losing weight or more carbs for training. Protein and carbs provide 4 calories per gram and fat provides 9, and the percentages must add up to 100%.

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