Evidence-Based Fitness Calculators
Professional tools for intermediate and advanced athletes. Built on peer-reviewed research and trusted methodologies.
RPE to % Chart
Convert perceived exertion to percentage of 1RM
Navy Body Fat Calculator
Estimate body fat % using the U.S. Navy circumference method
Wilks, DOTS & IPF GL Calculator
Compare powerlifting strength across weight classes with multiple formulas
Bulking Calculator
Lean bulk calories and macros for building muscle with minimal fat gain
Volume Calculator
Track MEV, MAV, and MRV training volume landmarks
Cutting Calculator
Fat loss calories and macros to preserve muscle while cutting
Protein Intake Calculator
Determine optimal daily protein based on your goals
Heart Rate Zones
Find optimal training zones for cardio work
RPE Load Calculator
Get the exact weight to load from your 1RM, target RPE, and reps
Bulk or Cut Quiz
Find out whether you should bulk, cut, or recomp based on your body fat and goals
BMI & WHtR Calculator
Assess health indicators with BMI and Waist-to-Height Ratio
TDEE & Macro Calculator
Calculate daily calorie needs and optimal macronutrient ratios
One Rep Max Calculator
Find your theoretical maximum strength from submaximal lifts
Body Recomposition Calculator
Build muscle and lose fat simultaneously with personalized recomp plan
Calorie Calculator
Simple daily calorie needs for weight loss, maintenance, or muscle gain
Workout Split Generator
Get evidence-based training split recommendations
Sleep Cycle Calculator
Find optimal sleep and wake times based on 90-minute sleep cycles
Hydration Calculator
Calculate daily fluid requirements based on activity
Training Programs
Evidence-based program calculators for systematic training progression
Why Choose FitnessCalcs?
Evidence-Based
All formulas backed by peer-reviewed research and trusted methodologies
Mobile-First
Optimized for use anywhere - at the gym, at home, or on the go
Lightning Fast
Instant calculations with no server round-trips or loading delays