Free Calculators

Science-based, fast and free tools for your nutrition and health goals — no sign-up, and your data never leaves your device.

BMR Calculator

Basal metabolism & daily calories

Calculated 12,934 times Open

Macro Splitter

Protein · carb · fat gram breakdown

Calculated 9,789 times Open

BMI Calculator

Body mass index & healthy range

Calculated 13,564 times Open

Ideal Weight

Your ideal weight range for your height

Calculated 11,965 times Open

Daily Water Intake

How much water you need by weight and activity

Calculated 11,243 times Open

Body Fat Percentage

With a tape measure (US Navy method)

Calculated 7,947 times Open

Calorie Deficit

Daily calories & deficit for your goal

Calculated 10,510 times Open

Protein Needs

Your daily protein (g) target

Calculated 9,100 times Open

TDEE Calculator

Your total daily calorie burn

Calculated 8,538 times Open

Weight-Loss Timeline

How many weeks will it take to reach your goal, by what date, and with how big a daily calorie deficit?

Calculated 7,381 times Open

Waist-to-Height Ratio

Divide your waist by your height; the healthy limit is half your height (0.5). See your Ashwell risk band and your target waist.

Calculated 5,347 times Open

Waist-to-Hip Ratio

Work out your WHR from your waist and hip measurements and see your risk category against WHO thresholds by sex.

Calculated 4,956 times Open

Fiber Needs

Calculate how many grams of fiber you need each day based on your daily calories.

Calculated 5,780 times Open

Sugar Limit

Based on your daily calories, calculate the WHO free-sugar upper limit (10%) and ideal amount (5%) in grams and teaspoons.

Calculated 6,350 times Open

Lean Body Mass

Estimate your lean body mass (muscle, bone, organs, water) and fat mass from your height and weight.

Calculated 4,632 times Open

Pregnancy Weight Gain

Recommended total weight gain and weekly rate based on your pre-pregnancy BMI (IOM 2009).

Calculated 3,984 times Open

Calories Burned

Estimate the calories you burn by activity type, body weight and duration using the MET method.

Calculated 6,834 times Open

Body Surface Area

BSA (m²) with the Mosteller formula

Calculated 3,789 times Open

Child BMI Percentile

Child BMI percentile by age and sex

Calculated 4,639 times Open

FFMI Calculator

Height-adjusted lean muscle mass index

Calculated 3,627 times Open

Breastfeeding Nutrition

Daily calories, protein and fluid for a nursing mother

Calculated 3,512 times Open

Alcohol Calorie Calculator

Calories in a drink — beer, wine, vodka, cocktails

Calculated 6,158 times Open

A1c – Average Blood Sugar

Convert your HbA1c value into average blood sugar (eAG), mmol/L and the IFCC unit; see the ADA status.

Calculated 4,838 times Open

Caffeine Limit

Daily safe caffeine limit (EFSA) and cup equivalents based on age, status, and weight.

Calculated 5,301 times Open

Total Body Water

Calculate total body water in liters and as a percentage of body weight with the Watson formula.

Calculated 4,004 times Open

eGFR Calculator

Find your kidney filtration rate and KDIGO stage with CKD-EPI 2021 (race-free).

Calculated 3,648 times Open

Body Roundness Index (BRI)

Calculate BRI, which reflects central (visceral) fat from your height and waist circumference better than BMI.

Calculated 5,714 times Open

Relative Fat Mass (RFM)

DXA-close body fat percentage estimate from height and waist — an alternative to the US Navy method.

Calculated 4,475 times Open

Bristol Stool Scale

Pick your stool type on the 7-point Bristol scale and get a bowel-transit and nutrition read-out.

Calculated 3,866 times Open

Urine Color Hydration Check

Pick your urine shade and see your fluid status on the Armstrong scale, plus what to do about it.

Calculated 4,148 times Open

SCOFF Eating Disorder Screening Test

Pre-screen your eating disorder risk with 5 short yes/no questions (SCOFF, not a medical diagnosis).

Calculated 4,581 times Open

EAT-26 Eating Attitudes Test

Screen for eating disorder risk with the 26-item international eating attitudes scale (not a diagnosis).

Calculated 4,212 times Open

Sweat Rate & Fluid Loss Calculator

Calculate your hourly sweat loss and rehydration needs from your pre- and post-workout weight difference.

Calculated 3,746 times Open

In-Exercise Carbohydrate Needs

Find your hourly carbohydrate (gel/drink) needs based on exercise duration, using ACSM guidelines.

Calculated 3,601 times Open

IPAQ Physical Activity Test

Measure your weekly activity in MET-minutes with the WHO-endorsed 7-question IPAQ (low/moderate/high).

Calculated 4,068 times Open

FINDRISC Diabetes Risk Test

Estimate your 10-year type 2 diabetes risk with the 8-question FINDRISC — no blood test needed.

Calculated 3,841 times Open

Carbohydrate Counting Calculator

Convert grams of carbohydrate into exchanges (15 g = 1) and calories (4 kcal/g); subtract fiber for net carbs.

Calculated 4,283 times Open
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