Performance calculators
Deterministic fitness math for lifters and runners.
46 calculators for FFMI, DOTS, 1RM, VO2 max, Zone 2, race times, and recovery. Every formula sourced, every limit named.
Free · Private · No signup · 46 tools
Pick your goal
Optimize Body Composition
Dial in calorie targets for recomposition — preserve strength while dropping body fat.
Build Strength & Muscle
Translate your calorie target into macro and protein plans optimized for strength gains.
Benchmark Your Strength
See where your lifts rank with DOTS, strength standards, and 1RM projections.
Plan Your Race
Predict race times, dial in training paces, and calibrate heart rate zones for distance running.
Recover Better
Align sleep, hydration, and intensity to improve training quality.
Understand Body Composition
Use simple body composition estimates to track direction over time.
Long-form articles
Evidence-backed, sourced, dated
The 2026 Lifter's Guide to Evidence-Based Programming
Volume, intensity, frequency, and specificity reviewed through the Schoenfeld meta-analyses and the hypertrophy literature. With dated caveats.
Zone 2 Training: What the Literature Actually Says
Polarised training, Seiler's 80/20, Stöggl & Sperlich 2014, and the San Millán mitochondrial framing — separated from the social-media version.
Protein for Lifters: The 2026 Dose-Response Meta-Analyses
Morton 2018 BJSM, Helms 2014 JISSN, and the current ceiling around 1.6–2.2 g/kg — plus what the bodybuilder-contest literature adds.
Quick picks
A useful answer in under a minute.
FFMI
Calculate Fat-Free Mass Index to gauge muscularity and compare against natural benchmarks.
DOTS/Wilks
Compare powerlifting strength across weight classes with IPF DOTS and Wilks-2020 coefficients.
1RM
Estimate one-rep max with Epley, Brzycki, and Lombardi formulas.
Body Recomp
Plan body-fat reduction pace, deficit targets, and protein needs around a timeline.
Race Predictor
Predict finish times across 5K, 10K, half marathon, and marathon from any known race result using Riegel's formula.
Heart Rate Zones
Calculate personalized training zones with the Karvonen method.
Strength Standards
Rank your lifts from Beginner to Elite based on bodyweight ratios.
Running Pace
Calculate pace per km and mile and project race finish times from one run.
All Tools 46
Nutrition
TDEE
Estimate your daily energy expenditure with Mifflin-St Jeor + activity factors.
BMR
Estimate basal metabolic rate and maintenance calories using Mifflin-St Jeor assumptions.
Macros
Convert calorie targets into protein, carbs, and fat grams for your goal.
Protein Intake
Get daily protein targets based on training level and goal.
Water Intake
Calculate daily water intake based on weight, activity level, and climate.
Fasting Planner
Plan protocol-based eating and fasting windows with a 24-hour timeline and 5:2 day picker.
Meal Macro Split
Convert daily macro targets into per-meal protein, carb, and fat execution numbers.
Creatine Intake
Estimate creatine maintenance and loading doses from body weight and training frequency.
Food to Exercise
See how long you need to exercise to burn off any food, personalized by bodyweight.
Macro Cycling
Calculate different macros for training days and rest days with carb cycling for recomp, lean bulk, or cut goals.
Strength
Progressive Overload
Project lifting progression with weekly overload and planned deload cycles.
1RM
Estimate one-rep max with Epley, Brzycki, and Lombardi formulas.
Strength Standards
Rank your lifts from Beginner to Elite based on bodyweight ratios.
DOTS/Wilks
Compare powerlifting strength across weight classes with IPF DOTS and Wilks-2020 coefficients.
Workout Volume
Calculate total training volume and compare against optimal ranges per muscle group.
Plate Loader
Calculate which weight plates to load on each side of a barbell to hit your target weight in kg or lbs.
DOTS/Wilks/GL
Compare DOTS, Wilks, and Goodlift scores side by side to see which system rates your powerlifting total highest.
RPE Converter
Convert RPE and reps to percentage of 1RM with a full interactive RPE chart based on the Tuchscherer table.
Strength Percentile
Find out where your squat, bench, deadlift, or OHP ranks against other lifters by bodyweight and sex.
Meet Attempts
Plan powerlifting meet attempts with opener, second, and third attempt suggestions based on 1RM and confidence.
Cardio
Running Pace
Calculate pace per km and mile and project race finish times from one run.
VO₂ Max
Estimate aerobic capacity with Cooper run, Rockport walk, or no-exercise questionnaire methods.
Walking Calories
Estimate calories burned from walking using speed, duration, body weight, and incline.
Calories Burned
Estimate exercise calorie burn from body weight, duration, MET intensity, and incline.
RHR
Assess cardiovascular fitness from your resting heart rate — classification, cardio age, and improvement targets.
Swim Pace
Calculate swim pace, total time, or distance with SWOLF and effort-zone context.
Run Training Paces
Get personalized Easy, Tempo, Threshold, Interval, and Speed training paces from a recent race time using the Daniels VDOT method.
Race Predictor
Predict finish times across 5K, 10K, half marathon, and marathon from any known race result using Riegel's formula.
FTP Zones
Calculate your 7 Coggan power training zones from FTP or a 20-minute test result with W/kg ratio.
Treadmill Pace
Convert treadmill speed to running pace with incline-adjusted flat equivalent, projected race times, and calorie estimates.
Zone 2 HR
Calculate your Zone 2 heart rate with Maffetone, Karvonen, % Max HR, and lactate threshold methods compared side by side.
Body Composition
BMI
Calculate BMI quickly with a plain-language range explanation and limitations.
Body Fat %
Estimate body fat percentage using the U.S. Navy circumference method.
Ideal Weight
Compare Devine, Robinson, Miller, and Hamwi formulas as a realistic range.
Waist-to-Hip Ratio
Calculate waist-to-hip ratio and assess body composition using WHO guidelines.
FFMI
Calculate Fat-Free Mass Index to gauge muscularity and compare against natural benchmarks.
LBM
Estimate lean body mass using Boer, James, Hume, and Peters formulas from height and weight.
Flex Score
Estimate your flexibility percentile and rating from a sit-and-reach test score, adjusted for age and sex.
Muscle Potential
Estimate your natural muscular potential with the Casey Butt model and see how close you are to your genetic limit.
Recovery
Heart Rate Zones
Calculate personalized training zones with the Karvonen method.
Sleep
Calculate optimal bed and wake times based on 90-minute sleep cycles.
Sweat Rate
Calculate your personal sweat rate from pre/post-exercise weigh-ins and estimate fluid and sodium losses using ACSM guidelines.
Sleep Debt
Track 7 nights of sleep to calculate accumulated sleep debt with a recovery timeline and quality assessment.
Planning
Calorie Deficit
Estimate required daily calorie deficit for a target timeline and bodyweight change.
Body Recomp
Plan body-fat reduction pace, deficit targets, and protein needs around a timeline.
Hybrid Planner
Build a weekly schedule that balances running and lifting with interference warnings and recovery guidance.