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Fitness calculators

Free and instant — no sign-up. Run the numbers, then let your AI coach turn them into a plan that adapts each week.

Training programs17

5/3/1 Calculator →Plan a full 5/3/1 cycle: training maxes, all four weeks, AMRAP rep targets.Full-Body Workout Plan →Three full-body sessions a week — the fastest start for a new lifter.5×5 Workout Program →Two alternating full-body sessions, adding weight every session.Upper / Lower Split →Four days a week — each half of the body heavy once and lighter once.Push / Pull / Legs Routine →Six days a week, two rotations — one at volume, one heavier.Wave Progression Program →Percentage waves on a training max — four main lifts, four-week cycles.Walk-to-Run 5K Plan →Nine weeks of jog/walk intervals to a continuous 5 km.8-Week Bench Press Program →Heavy, volume, and speed bench days sized from your current 1RM.4-Day Split Routine →Chest and triceps, back and biceps, shoulders and arms, then legs.Beginner 10K Training Plan →Four training days a week, building from comfortable running to 10 km.8-Week 5K Training Plan →Intervals, tempo, easy, and long runs for a faster 5K.12-Week Half-Marathon Plan →Four runs a week with the long run building to 18 km.16-Week Sub-4 Marathon Plan →Four runs a week at a 5:41/km target pace, with long runs to 30 km.Ramadan Training Planner →Place training, hydration and protein between iftar and suhoor.Equipment inventory and program feasibility calculator →Check the equipment you have and your available training days to see which FitnessGrid programs run as written, which need a stated substitution, and which still need equipment.Fitness habit stack builder with minimum versions →Pair up to three routines you already do with small fitness habits, then keep a minimum version for days when the full action does not fit.Workout Plan Generator →A full training week from your days, level, goal and equipment.

Cardio61

Heart Rate Zones →Your max heart rate and five training zones, calculated from age.VO2 Max Calculator →Estimate aerobic capacity from the Cooper 12-minute run test.Cardio Fitness Score →Rate a VO2 max estimate against age and sex cardio-fitness bands.MAF Heart Rate Calculator →Calculate your Maffetone max aerobic heart rate and easy range.Calories Burned Calculator →Estimate calories burned for an activity from its MET, your weight, and time.Beep Test Calculator →Turn a 20 m shuttle run level and shuttle into an estimated VO2 max.Bruce Protocol Calculator →Estimate VO2 max from your total time on the Bruce treadmill test.Rockport Walk Test Calculator →Estimate VO2 max from a one-mile walk and the heart rate you finished on.Astrand Step Test Calculator →Estimate VO2 max from five minutes of stepping and your steady heart rate.Fitness Age Calculator →The age at which your VO₂ max is the population median — an honest lookup, not a questionnaire.Biological Age Calculator →Levine phenotypic age from nine standard blood-panel markers.VO₂ Max Percentile Calculator →Where your VO₂ max sits against published age and sex percentiles.Grip Strength Longevity Calculator →Your dynamometer reading against the norms mortality research keeps pointing at.Balance Age Calculator →One-leg stand time against age norms — the 10-second test, scored honestly.Sit and Reach Calculator →Score the box flexibility test against adult norms, box-zero handled.How Fit Are You →A percentile across the tests you can actually enter — quiz format, honest math.Karvonen Calculator →Target heart rate from heart-rate reserve, using your resting heart rate.FTP Calculator →Your FTP and the seven Coggan power zones from a 20-minute or ramp test.Wingate Test Calculator →Peak power, mean power and fatigue index from a 30-second Wingate.TSS Calculator →Training Stress Score from duration, normalized power and FTP.Normalized Power Calculator →Normalized power, intensity factor and variability index.Power to Weight Calculator →W/kg at FTP and across 5 s, 1 min and 5 min efforts.Harvard Step Test Calculator →Physical fitness index from your recovery pulse counts.Queens College Step Test Calculator →VO2 max from a three-minute step test recovery heart rate.Critical Swim Speed Calculator →CSS threshold pace from 400 m and 200 m time trials.SWOLF Calculator →Swim efficiency from strokes and seconds per length.Swim Set Calculator →Build a swim set on send-off intervals from your CSS pace.Session RPE Calculator →Training load, monotony and strain from duration and RPE.Maximum Heart Rate Calculator →Predict max heart rate from age across four equations, not just 220 − age.1.5 Mile Run Test Calculator →Estimate VO2 max from the 1.5 mile (2.4 km) run used by military and police standards.Yo-Yo Intermittent Recovery Test Calculator →Convert a Yo-Yo IR1 or IR2 distance into estimated VO2 max.Balke Treadmill Test Calculator →Estimate VO2 max from time on the Balke walking treadmill protocol.Cooper Test Calculator →Score a 12-minute run: VO2 max plus your band on Cooper's own table.Concept2 Pace Calculator →Split, watts, calories and equivalent times for any erg piece.HYROX Time Calculator →Turn a target finish into run splits and station-by-station budgets.Critical Power Calculator →Fit CP and W-prime from two maximal efforts.Sleep Calculator →Bedtimes and wake times aligned to whole 90-minute sleep cycles.Sleep Debt Calculator →Add up a week of short nights and see what clearing it costs.Chronotype Quiz →Five questions from the validated rMEQ — morning, evening or intermediate.Fitness Personality Quiz →Twenty questions, four traits, sixteen animals — and what each one should train like.HRV Calculator →Your rolling HRV read against your own baseline, not an absolute scale.Resting Heart Rate Calculator →Trend, baseline and elevation — without the unsourced fitness chart.Orthostatic Test Calculator →The lying-to-standing heart rate rise, and what the threshold does not mean.Blood Pressure Calculator →One reading, categorised under both the American and European guidelines.Jet Lag Calculator →Days to adjust, and when to seek or avoid light on arrival.Sweat Sodium Calculator →How much sodium a session actually costs you, in mg and in salt.Sauna Calculator →Where your sauna habit sits against the Finnish cohort's own bands.Cold Plunge Calculator →Whether cold helps or interferes, given your goal and your timing.DOMS Calculator →When muscle soreness should peak and when it should be gone.Return to Running Calculator →A walk-run ladder governed by the pain rule that has evidence behind it.Recovery Score Calculator →HRV, sleep and resting heart rate combined — with the weights shown.Beep Test Level Table →All 21 levels with speed, shuttles, distance, and estimated VO₂ max.Testosterone Quiz →The ten-item ADAM screen plus separate lifestyle factors to act on.Recovery Readiness Quiz →The four-item Hooper index with an optional resting-heart-rate check.Overtraining Risk Quiz →Eight consensus signals, with OTS kept as a diagnosis of exclusion.Max Heart Rate by Age Table →Maximum heart rate from 18 to 80 across four formulas, with training zones.Cooper Test Table →12-minute run norms by age and sex, with an even-pace and VO₂ max table.VO₂ Max Table by Age →Cooper Institute VO₂ max norms by age and sex, with the average for each age.SWOLF Table →SWOLF scores by strokes and seconds for 25 m and 50 m pools, with level bands per pool length.Yo-Yo Test Table →IR1 and IR2 distances converted to VO₂ max, with the fitness rating each earns.Watts per Kg Table →FTP to W/kg for every body weight, with the Coggan rider categories for men and women.

Body composition29

Body Fat Calculator →Estimate your body-fat % from measurements (US Navy method).BMI Calculator →Your Body Mass Index and WHO weight category from height and weight.Ideal Weight Calculator →Your Devine ideal body weight from height and sex — a reference point.FFMI Calculator →Fat-Free Mass Index — BMI's muscle-aware cousin for lean mass.Body Composition Calculator →Fat mass, lean mass, BMI, FFMI, normalized FFMI, and FMI in one view.Lean Body Mass Calculator →Split your weight into lean mass and fat mass from your body-fat %.Body Surface Area Calculator →Your body surface area in square metres (Mosteller formula).Waist-to-Height Ratio →A better-than-BMI central-adiposity screen from waist and height.YMCA Body Fat Calculator →Estimate your body-fat % from two numbers: your waist and your weight.RFM Calculator →Relative Fat Mass — body-fat % from height and waist alone.Body Recomposition Calculator →Lose fat and build muscle at once — rate, timeline, calories, protein.Jackson-Pollock 3-Site Calculator →Body fat % from three skinfolds — the classic caliper method.Jackson-Pollock 7-Site Calculator →Body fat % from seven skinfolds — the research-grade caliper method.Durnin & Womersley Calculator →Body fat % from four skinfolds using age-banded constants.ABSI Calculator →A Body Shape Index and z-score against population norms.Body Density Calculator →Convert body density to body-fat % with Siri and Brožek.Skeletal Muscle Mass Calculator →Estimate actual muscle mass from height, weight, age and sex — not lean mass.Waist-to-Hip Ratio Calculator →Divide waist by hips and read the result against the WHO cutoffs.Body Frame Size Calculator →Small, medium or large build, from wrist circumference and height.Ponderal Index Calculator →Weight divided by height cubed, shown next to your BMI.Adjusted Body Weight Calculator →Devine ideal body weight and the adjusted weight derived from it.Conicity Index Calculator →How much wider than a cylinder of your mass you are at the waist.Somatotype Calculator →Endomorphy, mesomorphy and ectomorphy by the Heath-Carter method.Jackson-Pollock 4-Site Calculator →Body fat from four skinfolds, using the Ward equation for women.Asian BMI Calculator →BMI against the WHO Asia-Pacific cutoffs, where overweight starts at 23.Body Fat Scale Accuracy Calculator →The real range behind a body fat reading, by measurement method.Sitting Height Ratio Calculator →Cormic index, leg length and what your proportions mean for lifting.FFMI Chart →Normalized FFMI bands and lean mass at four common heights.Body Composition Scale Reader →Interpret eight readings from Tanita, Omron and InBody reports.

Nutrition14

Strength28

1RM Calculator →Estimate your one-rep max and get a full %-of-1RM training table.Plate Calculator →Which Olympic kg plates to load on each side to hit a target weight.Wilks Calculator →Score a powerlifting total against bodyweight — Wilks, DOTS, and IPF GL.RPE Calculator →Convert RPE and reps into a percentage of your 1RM — and back again.Grip Strength Calculator →See where a handgrip dynamometer reading sits against age and sex norms.Strength Standards Calculator →See your level — untrained to elite — for squat, bench, deadlift, and press.DOTS Calculator →Score a powerlifting total against bodyweight — the formula that replaced Wilks.IPF GL Points Calculator →Score a total on IPF GL points, the current IPF ranking formula.Sinclair Calculator →Compare Olympic weightlifting totals across bodyweights.Vertical Jump Power Calculator →Peak and average anaerobic power from jump height.Volume Landmarks Calculator →MEV, MAV and MRV weekly set targets for each muscle group.Vertical Jump Calculator →Measure your vertical from a reach test or hang time, with norms.Grip Strength Norms Table →Grip strength means and one-SD bands by age and sex, in kg and lb.1RM Percentage Chart →Epley and Brzycki percentages for 1–15 reps plus kg load rows.Strength Standards Table →Squat, bench, deadlift, and press targets by bodyweight and sex.1RM Formula Comparison Calculator →Compare seven e1RM equations, their mean and formula spread.AMRAP Calculator →Turn an AMRAP set into e1RM and a percentage-based next load.Strength Ratio Calculator →Compare squat, bench and deadlift ratios and find the lagging lift.Strength Symmetry Calculator →Check left:right and matched push:pull strength differences.Volume Load Calculator →Calculate exercise tonnage, session total and relative volume.Velocity-Based Training Calculator →Fit a load–velocity profile and estimate 1RM at the lift's MVT.Muscle Imbalance Quiz →Ten training signals for push, quad, and side-to-side imbalance profiles.Training Level Quiz →Training age, consistency, and optional relative lifts choose a programming level.Reshel Coefficient Calculator →Score a total from the full GPA quarter-kilogram Reshel charts.Schwartz–Malone Points Calculator →Score a total with Schwartz for men or Malone for women.Glossbrenner Points Calculator →Score a total with the shared WPC-family, WABDL and 100% RAW formula.Functional Movement Screen composite scorer →Enter the trained rater's 0–3 scores for all seven FMS patterns, including both sides and pain-clearing tests, to calculate the 0–21 composite.RPE Chart →The full RPE to % of 1RM chart for 1–12 reps at RPE 6–10, with loads for common prescriptions.

Running16

Country-specific tools7