GymCalc AI

BMI Calculator

Calculate body mass index from weight and height with instant category guidance.

Nutrition

TDEE Calculator

Estimate maintenance calories from BMR, activity level, age, gender, height, and weight.

Fat Loss

Calorie Deficit Calculator

Turn maintenance calories into a realistic fat loss target and weekly loss estimate.

Nutrition

Macro Calculator

Split calories into protein, carbs, and fats based on your training goal.

Nutrition

Protein Intake Calculator

Find daily protein needs for general health, training, and muscle growth.

Recovery

Water Intake Calculator

Calculate daily hydration needs based on body weight, training time, and climate.

Body Fat Calculator

Use neck, waist, hip, and height measurements to estimate body fat percentage.

Lean Body Mass Calculator

Estimate lean mass from weight and body fat percentage for smarter physique tracking.

Strength

One Rep Max Calculator

Estimate your max lift and training percentages without testing a true max.

Strength

Workout Volume Calculator

Measure total lifting tonnage for a set, exercise, or workout.

FFMI Calculator

Estimate fat free mass index and see a practical muscularity category.

Performance

Heart Rate Zone Calculator

Find heart rate zones from age for cardio, fat burn, peak, and recovery training.

Fat Loss

Fat Loss Timeline Calculator

Estimate how long it may take to reach a target weight using a daily calorie deficit.

Start with maintenance

Estimate TDEE first, then choose a deficit, surplus, or recomposition target based on the trend you want.

Protect lean mass

Use protein, strength training, and reasonable calorie changes to keep performance moving while body composition changes.

Track weekly averages

Daily weight and heart rate data can be noisy. Weekly trends make better decisions than single snapshots.

Fitness Guides

Articles

Fat Loss - 6 min read

Best Calorie Deficit for Fat Loss

Learn how to choose a calorie deficit that burns fat while preserving strength, energy, and adherence.

Nutrition - 5 min read

How Much Protein Do You Need?

A practical guide to daily protein intake for muscle gain, fat loss, athletes, and beginners.

Training - 7 min read

Best Workout Split for Beginners

Compare full body, upper/lower, and push-pull-legs training splits for new lifters.

Supplements - 5 min read

Creatine Guide for Lifters

Understand creatine loading, maintenance dosing, timing, safety basics, and how it supports strength training.