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 OpenMacro Splitter
Protein · carb · fat gram breakdown
Calculated 9,789 times OpenBMI Calculator
Body mass index & healthy range
Calculated 13,564 times OpenIdeal Weight
Your ideal weight range for your height
Calculated 11,965 times OpenDaily Water Intake
How much water you need by weight and activity
Calculated 11,243 times OpenBody Fat Percentage
With a tape measure (US Navy method)
Calculated 7,947 times OpenCalorie Deficit
Daily calories & deficit for your goal
Calculated 10,510 times OpenProtein Needs
Your daily protein (g) target
Calculated 9,100 times OpenTDEE Calculator
Your total daily calorie burn
Calculated 8,538 times OpenWeight-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 OpenWaist-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 OpenWaist-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 OpenFiber Needs
Calculate how many grams of fiber you need each day based on your daily calories.
Calculated 5,780 times OpenSugar 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 OpenLean Body Mass
Estimate your lean body mass (muscle, bone, organs, water) and fat mass from your height and weight.
Calculated 4,632 times OpenPregnancy Weight Gain
Recommended total weight gain and weekly rate based on your pre-pregnancy BMI (IOM 2009).
Calculated 3,984 times OpenCalories Burned
Estimate the calories you burn by activity type, body weight and duration using the MET method.
Calculated 6,834 times OpenBody Surface Area
BSA (m²) with the Mosteller formula
Calculated 3,789 times OpenChild BMI Percentile
Child BMI percentile by age and sex
Calculated 4,639 times OpenFFMI Calculator
Height-adjusted lean muscle mass index
Calculated 3,627 times OpenBreastfeeding Nutrition
Daily calories, protein and fluid for a nursing mother
Calculated 3,512 times OpenAlcohol Calorie Calculator
Calories in a drink — beer, wine, vodka, cocktails
Calculated 6,158 times OpenA1c – 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 OpenCaffeine Limit
Daily safe caffeine limit (EFSA) and cup equivalents based on age, status, and weight.
Calculated 5,301 times OpenTotal Body Water
Calculate total body water in liters and as a percentage of body weight with the Watson formula.
Calculated 4,004 times OpeneGFR Calculator
Find your kidney filtration rate and KDIGO stage with CKD-EPI 2021 (race-free).
Calculated 3,648 times OpenBody Roundness Index (BRI)
Calculate BRI, which reflects central (visceral) fat from your height and waist circumference better than BMI.
Calculated 5,714 times OpenRelative Fat Mass (RFM)
DXA-close body fat percentage estimate from height and waist — an alternative to the US Navy method.
Calculated 4,475 times OpenBristol 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 OpenUrine 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 OpenSCOFF 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 OpenEAT-26 Eating Attitudes Test
Screen for eating disorder risk with the 26-item international eating attitudes scale (not a diagnosis).
Calculated 4,212 times OpenSweat Rate & Fluid Loss Calculator
Calculate your hourly sweat loss and rehydration needs from your pre- and post-workout weight difference.
Calculated 3,746 times OpenIn-Exercise Carbohydrate Needs
Find your hourly carbohydrate (gel/drink) needs based on exercise duration, using ACSM guidelines.
Calculated 3,601 times OpenIPAQ Physical Activity Test
Measure your weekly activity in MET-minutes with the WHO-endorsed 7-question IPAQ (low/moderate/high).
Calculated 4,068 times OpenFINDRISC Diabetes Risk Test
Estimate your 10-year type 2 diabetes risk with the 8-question FINDRISC — no blood test needed.
Calculated 3,841 times OpenCarbohydrate 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 OpenNo matching tools found.
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