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Health calculators that are actually beautiful

Instant, accurate answers about your calories, BMI, hydration, and ideal weight — with interactive charts, milestone forecasts, and zero clutter.

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Calorie Deficit Calculator

Find your maintenance calories (TDEE), your ideal daily calorie target, and an interactive week-by-week weight loss forecast with a predicted goal date.

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BMI Calculator

Calculate your Body Mass Index instantly with a beautiful visual scale, see your category, and understand what your score actually means for your health.

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Water Intake Calculator

Get a personalized daily water recommendation based on your weight, activity level, and climate — in litres and glasses, with a visual hydration tracker.

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Macro Calculator

Calculate your daily macros — protein, carbs, and fat — for your goal, with a personalized calorie target and a visual breakdown.

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Body Fat Calculator

Estimate your body fat percentage with the U.S. Navy method, see your fitness category, and get your fat mass and lean mass breakdown.

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Reaction Time Test

Test your reaction time — click the instant the box turns green and see your speed in milliseconds, with your best and average across multiple tries.

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Ideal Weight Calculator

Estimate your ideal body weight using four peer-reviewed formulas (Devine, Robinson, Miller, Hamwi) plus your healthy BMI range, visualized beautifully.

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Peer-reviewed formulas

Every calculation uses published, citable science — Mifflin–St Jeor, WHO BMI ranges, EFSA hydration guidance, and four ideal-weight equations.

Interactive forecasts

Not just a number. See week-by-week weight loss timelines, milestone dates, and animated visual scales that make results instantly clear.

Private by design

Everything runs in your browser. Your weight, height, and goals are never sent to a server or stored anywhere.

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Nutrition

How to Count Macros for Weight Loss: A Beginner's Guide

What macros are, how to set your protein, carb, and fat targets for fat loss, and how to track them without losing your mind — a simple step-by-step start.

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Weight Loss

How to Calculate a Calorie Deficit (Step-by-Step)

A clear, step-by-step guide to working out your own calorie deficit — from maintenance calories to your daily target — with a worked example you can copy.

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Hydration

How Much Water Should You Drink to Lose Weight?

Water won't melt fat on its own, but smart hydration genuinely supports weight loss. Here's how much to drink, when, and why it helps.

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Nutrition

What Is a Good BMI for Your Age?

The healthy BMI range is the same for all adults — but age changes how you should interpret the number. Here's what actually matters.

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Weight Loss

How Many Calories Should I Eat to Lose Weight?

A practical, science-based guide to finding your personal calorie target for sustainable weight loss — without crash dieting.

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Nutrition

What Is a Healthy BMI? Understanding the Numbers

What BMI actually measures, where the healthy range comes from, and when the number can mislead you.

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Hydration

How Much Water Should You Drink Daily?

Forget the 8-glasses rule. Here's how to calculate your real daily water needs based on your body, activity, and climate.

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Weight Loss

How Long Does It Take to Lose 50 Pounds?

Realistic timelines for losing 50 lbs safely, what affects your rate of loss, and how to map your own milestone schedule.

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