These tools estimate the everyday numbers behind fitness and nutrition planning — body mass index, basal metabolic rate, daily calorie needs, body fat percentage, and training paces. Each one shows the underlying formula (Mifflin-St Jeor for BMR, standard activity multipliers for TDEE) so the estimate isn't a mystery number.
Start with BMI or BMR if you're establishing a baseline, or TDEE and the calorie counter if you're planning a cut, maintenance, or bulk. These are population-level estimates, not a substitute for a metabolic test or a clinician's guidance for a medical condition.
Health & fitness
Pick a tool below. Each page includes the formula, step-by-step logic, and examples—so you can use the result with confidence.
Showing 9 tools
Subcategory
Body Metrics
2 toolsBMR & TDEE Calculator
Estimate basal metabolic rate and daily calories using established equations and activity factors. Runs locally in your browser.
Body Fat Percentage Calculator
Estimate body fat % from tape measurements using the US Navy method. See your category, fat mass, and lean mass — no calipers or gym required.
Subcategory
Fitness
3 toolsBMI Calculator
Compute Body Mass Index from height and weight in metric or imperial. Fully client-side — no account, uploads, or remote storage.
Running Pace Calculator
Calculate your running pace, finish time, or distance instantly. Get race time predictions for 5K, 10K, half marathon, and marathon. Supports km and miles..
One-Rep Max (1RM) Calculator
Estimate your 1RM from any submaximal lift. Uses Epley, Brzycki, and Lombardi formulas. Includes a full training percentage table for strength programming.
Subcategory
Nutrition
4 toolsCalorie & TDEE Calculator
Estimate calories burned by activity, duration, and body weight using MET tables. Fully client-side — no account, uploads, or remote storage.
Water Intake Calculator
Calculate how much water you should drink per day based on your weight, activity level, and climate. See results in liters, oz, and number of glasses.
TDEE Calculator
Calculate your Total Daily Energy Expenditure and daily calorie target for weight loss, maintenance, or muscle gain. Uses the Mifflin-St Jeor formula.
Macro Calculator
Calculate your daily protein, carb, and fat targets in grams from your calorie goal, body weight, and goal. Works for fat loss, maintenance, and muscle gain.