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Free fitness calculators

Science-based nutrition, body, strength, endurance, and recovery calculators. Fast, private, and browser-only.

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restaurantNutrition & Energy

local_fire_departmentTDEE CalculatorFind the calories you burn in a day, then set a cut, maintain, or bulk target.boltBMR CalculatorThe energy your body burns at complete rest — the floor under every calorie goal.trending_downCalorie Deficit CalculatorTurn a target weekly loss into a safe daily calorie goal.pie_chartMacro CalculatorSplit your calories into protein, fat, and carbs — per day and per meal.egg_altProtein Intake CalculatorHow much protein your goal, training, and age actually call for.water_dropWater Intake CalculatorA daily fluid target from your body weight and training load.calendar_view_weekCalorie Cycling CalculatorSplit a weekly calorie target into higher training days and lower rest days without changing the average.elderlyProtein Calculator for 50+The higher protein target older muscle needs to fight age-related loss, split across your meals.health_and_safetyGLP-1 Protein CalculatorHow much protein to eat to protect muscle during rapid weight loss on a GLP-1 medication.

accessibility_newBody Composition

monitor_weightBMI CalculatorYour body mass index against both WHO and Asian cut-offs.percentBody Fat CalculatorEstimate body-fat percentage from tape measurements or skinfolds.balanceIdeal Weight CalculatorFour classic formulas for a healthy weight — and why they disagree.calendar_monthWeight-Loss Timeline PlannerSee a realistic date for your goal weight at a safe pace.straightenWaist-to-Height Ratio CalculatorA quick central-fat screen that predicts health risk better than BMI — keep it under half your height.monitoringLean Body Mass CalculatorEstimate lean mass and fat mass with the Boer, James, and Hume formulas.syncBody Recomposition CalculatorPlan simultaneous fat loss and muscle gain, with realistic rates by training experience.

fitness_centerStrength

fitness_centerOne-Rep Max CalculatorEstimate your 1RM and read off working weights from 50% to 100%.leaderboardStrength Standards CalculatorSee how your squat, bench, deadlift, or press ranks against population strength bands.albumBarbell Plate CalculatorWork out exactly which plates to load per side for any target weight, in kg or lb.workspace_premiumWilks & DOTS CalculatorScore your powerlifting total against bodyweight with both the Wilks and DOTS coefficients.speedRPE to Percentage CalculatorConvert an RPE and rep count into a percentage of your 1RM, or find the weight for a target RPE.

directions_runEndurance & Activity

directions_runCalories Burned CalculatorMET-based calorie burn for 40+ activities.timerRunning Pace CalculatorTurn a distance and time into pace per km and mile, plus even-pace splits from 5K to marathon.sports_scoreRace Time PredictorPredict your finish time at a new distance from one recent race using the Riegel formula.cardiologyHeart Rate Zone CalculatorFive training zones from %HRmax or the Karvonen method, with the zone-2 range spelled out.pulmonologyVO₂ Max CalculatorEstimate your VO₂ max from a Cooper run or Rockport walk test, or read your watch's number against the norms.directions_walkSteps to Calories CalculatorTurn your daily step count into calories burned and distance covered, adjusted for pace and stride.pregnant_womanPregnancy Exercise Heart Rate CalculatorA conservative moderate-intensity heart-rate zone for exercising during pregnancy, with the talk test as your main guide.

bedtimeRecovery & Sleep

ecg_heartHRV Normal Range CalculatorSee the typical HRV range for your age and where your watch's RMSSD or SDNN falls.bedtimeSleep Cycle CalculatorFind the bedtimes or wake times that let you wake between 90-minute sleep cycles, not mid-cycle.

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