10 free tools
Fitness & Sports tools built for real work
Transparent fitness and sports calculators for pace, training estimates, body metrics and exercise planning with clear limitations. Every tool is designed to expose its inputs and outputs clearly instead of hiding the logic behind a vague score.
▲BMI CalculatorCalculate adult BMI from metric or US measurements, show the standard BMI category and explain the limits of BMI as a screening measure.→▲Body Fat Estimate CalculatorEstimate body-fat percentage from circumference measurements using a Navy/DoD-style logarithmic method with metric or inch inputs.→▲Exercise Calorie Burn CalculatorEstimate exercise energy expenditure from body weight, activity MET value and duration using the standard MET calorie equation.→▲Heart Rate Zone CalculatorEstimate exercise heart-rate zones with either percent-of-max or heart-rate-reserve calculations using editable age and resting heart rate.→▲One-Rep Max CalculatorEstimate one-repetition maximum from a submaximal set using Epley and Brzycki equations and compare percentage-based training loads.→▲Running Pace CalculatorConvert running distance and finish time into pace per kilometre, pace per mile, speed and projected finish times.→▲Sports Hydration CalculatorEstimate sweat rate from pre/post body mass, fluid intake, urine output and exercise duration, with visible body-mass change.→▲Strength Score CalculatorCalculate estimated 1RM, relative strength versus body weight and progress toward a user-defined strength target without invented ranking tiers.→▲Swim Pace CalculatorConvert swim distance and time into pace per 100, pace per 50, average speed and same-pace projections for common pool distances.→▲TDEE / Calorie Needs CalculatorEstimate resting energy expenditure with the Mifflin-St Jeor equation and multiply by an editable activity factor for TDEE.→
Why ToolboxKart Fitness & Sports tools?
Fast interfaces, plain-language explanations, mobile-friendly layouts and no unnecessary account wall for the utilities in this release.
Tool first
The working interface appears before long-form SEO content, so you can finish the task quickly.
Transparent logic
Calculators disclose formulas or assumptions where they matter, and analyzers avoid pretending subjective checks are scientific facts.
Reusable results
Copyable output and clean formatting are included where they improve the workflow.