Free Online Tools for Fitness Enthusiasts
Optimize your fitness journey — calculate BMI, track calories and macros, estimate protein needs, measure body fat, find target heart rate zones, and pace your runs.
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BMI Calculator
Calculate your Body Mass Index with visual BMI scale
Use tool →Body Fat Calculator
Estimate body fat percentage using the US Navy method and BMI formula
Use tool →Calorie Calculator
Calculate daily calories (TDEE/BMR) with macro breakdowns for your goals
Use tool →Calories Burned Calculator
Calculate calories burned across 95+ activities organized in 9 categories using MET values, with heart rate zone estimation and weekly planning
Use tool →Heart Rate Zone Calculator
Calculate your target heart rate zones for optimal training using the Karvonen formula
Use tool →Macro Calculator
Calculate daily protein, carbs, and fat needs for your fitness goal
Use tool →Protein Calculator
Calculate your optimal daily protein intake based on weight, activity level, and fitness goals
Use tool →Running Pace Calculator
Calculate running pace, finish time, or distance with split times
Use tool →TDEE Calculator
Calculate your Total Daily Energy Expenditure based on BMR, activity level, and body composition
Use tool →Frequently Asked Questions
What fitness tools does NexTool offer?▾
NexTool provides a complete suite of free fitness tools: BMI calculator, calorie and TDEE calculator, macro nutrient splitter, protein intake estimator, body fat percentage calculator, target heart rate zone finder, and running pace calculator.
How do I calculate my daily calorie needs?▾
Use our calorie calculator to find your Total Daily Energy Expenditure (TDEE). Enter your age, gender, height, weight, and activity level to get your maintenance calories, then adjust for weight loss or gain goals.
Can I calculate my ideal macronutrient split?▾
Yes. Our macro calculator takes your calorie target and preferred diet style (balanced, low-carb, high-protein, keto) and breaks it down into grams of protein, carbohydrates, and fat per day.
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