Health & Fitness Calculators
BMI, calories, macros, pregnancy dates and running pace — quick health maths.
BMI Calculator
Body mass index with healthy-weight range for your height.
Calorie Calculator
Daily calories for maintenance, loss or gain.
BMR & TDEE Calculator
Your BMR and daily burn at each activity level.
Body Fat Calculator (Navy)
Body fat % via the US Navy tape-measure method.
Macro Calculator
Protein/carb/fat grams from your calorie target and diet split.
Ideal Weight Calculator
Ideal weight from four formulas plus the BMI healthy band.
Water Intake Calculator
Daily water target from weight and activity.
Pregnancy Due Date Calculator
Due date (Naegele's rule) plus current week and trimester.
Ovulation Calculator
Ovulation day and fertile window for your cycle.
Running Pace Calculator
Pace, speed and finish-time predictions for any distance.
Alcohol Units & BAC Calculator
Units per drink, weekly total and a rough BAC estimate.
Sleep Calculator
Wake at the end of a 90-minute sleep cycle to feel less groggy.
Smoking Cost Calculator
The true financial cost of smoking — and what quitting saves.
Child Height Predictor
Adult height prediction from parents' heights.
Waist-to-Height Ratio Calculator
WHtR — keep your waist under half your height.
Weight Loss Percentage Calculator
% lost = (start − current) ÷ start × 100 — pounds or kilos, same maths.
Army Body Fat Calculator
Body fat % via the US Navy tape-measure method.
Body Weight % Calculator
% lost = (start − current) ÷ start × 100 — pounds or kilos, same maths.
TDEE Calculator
Mifflin-St Jeor BMR × activity multiplier — then the calorie targets for loss or gain.
One Rep Max Calculator
Enter a weight you lifted for reps — formulas estimate the true single.
VO2 Max Calculator
Two lab-free estimates: resting-heart-rate ratio or the Cooper 12-minute run.
Bench Press Calculator
Bench 1RM from a submaximal set — same Epley/Brzycki maths with a lift-specific table.
Marathon Pace Calculator
42.195km — pace for a target time, or the finish time your pace delivers.
Macro Calculator for Weight Loss
Protein/carb/fat grams from your calorie target and diet split.
Keto Macro Calculator
Protein/carb/fat grams from your calorie target and diet split.
Marathon Pace
42.195km — pace for a target time, or the finish time your pace delivers.
Running Pace Calculator
Pace, speed and finish-time predictions for any distance.
Bench Press Max Calculator
Bench 1RM from a submaximal set — same Epley/Brzycki maths with a lift-specific table.
Rep Max Calculator
Enter a weight you lifted for reps — formulas estimate the true single.
VO2 Max Estimator
Two lab-free estimates: resting-heart-rate ratio or the Cooper 12-minute run.
Macronutrient Calculator
Protein/carb/fat grams from your calorie target and diet split.
TDEE
Mifflin-St Jeor BMR × activity multiplier — then the calorie targets for loss or gain.
Weight Loss Calculator
Time to goal weight at a given daily deficit.
Bra Size Calculator UK
UK band + cup from underbust and bust measurements.
Body Surface Area Calculator
BSA via Mosteller: √(height × weight / 3600).
Pregnancy Calculator
Due date (Naegele's rule) plus current week and trimester.
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