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Nutrition calculators for smarter diet decisions

Estimate calories, macros, protein, body metrics, and recipe nutrition with tools built on established formulas. Clear results, transparent assumptions, no account required.

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The differentiator

Calorie cycling, planned by the week

Most tools give one flat daily number. Ours spreads your weekly deficit across higher and lower days, so training days and weekends fit the plan instead of breaking it. The weekly total stays exactly on target.

Plan your week

How it works

Three steps, then a plan you can act on

01

Enter your details

Add your stats, activity, and goal, or an ingredient list. Switch metric or imperial anytime; nothing is stored.

02

Review your estimate

See the number that matters with a short interpretation and the assumptions behind it, from Mifflin-St Jeor to USDA data.

03

Use it as a guide

Treat the result as a starting point and adjust from real progress over a few weeks. It is an estimate, not a diagnosis.

Results are estimates based on recognized formulas. See the methodology page for every equation and data source.

Clear calculations. Transparent methods.

Our calculators use recognized equations and published reference values. They are estimates, and real needs vary with metabolism, medical conditions, pregnancy, and medication. For personalized advice, speak with a doctor or registered dietitian.

  • Recognized formulas
    Mifflin-St Jeor and Katch-McArdle for energy, USDA FoodData Central for food.
  • Assumptions explained
    Each result names the equation it used and the key limits behind the number.
  • Metric and imperial
    Every tool switches units with one tap, with no account and no data stored.

Frequently asked questions

What is a nutrition calculator?

A nutrition calculator estimates a diet-related number from your inputs and a published formula. Ours cover calories, macros, protein, weight-loss progress, body composition, and recipe nutrition, each returning an estimate with the assumptions behind it.

Which calculator should I use to lose weight?

Start with the calorie deficit calculator for a daily target and timeline. Add the TDEE calculator for your maintenance calories, the macro calculator to split them, and the protein calculator to protect muscle while you lose fat.

How do I calculate my maintenance calories?

Use the TDEE and maintenance calories calculator. It applies the Mifflin-St Jeor equation to your sex, age, height, and weight, then multiplies by an activity factor to estimate the calories that hold your weight steady.

Can I calculate protein and macros together?

Yes. The macro calculator returns grams of protein, carbs, and fat from your calorie target, and the protein calculator focuses on your daily protein range and per-meal split. Together they give a full daily plan.

Are nutrition calculator results exact?

No. They are estimates from recognized equations and average reference values, usually within about 10 percent. Metabolism, medical conditions, and measurement error shift real needs, so adjust from your own results over time.