Fitness & Exercise Calculators
Optimize your training with calculators for one-rep max, heart rate zones, running pace, and VO2 max.
One Rep Max Calculator
Estimate your one-rep max using Epley, Brzycki, and Lombardi formulas.
Get startedHeart Rate Zone Calculator
Find your five training heart rate zones using the Karvonen formula.
Get startedPace Calculator
Calculate your running pace, speed, and predicted race finish times.
Get startedVO2 Max Calculator
Estimate your VO2 max and aerobic fitness level with the Cooper or Rockport test.
Get startedRace Time Predictor
Predict finish times for common race distances using the Riegel formula.
Get startedFrequently Asked Questions
What is a one-rep max and why does it matter?
Your one-rep max (1RM) is the maximum weight you can lift for a single repetition of a given exercise. Knowing your 1RM helps you program training percentages for strength, hypertrophy, or endurance work without needing to test a true max every session.
How do heart rate training zones work?
Heart rate zones divide your effort into five levels based on percentages of your maximum heart rate. Zone 1 is light recovery, Zone 2 builds aerobic base, Zone 3 improves endurance, Zone 4 increases lactate threshold, and Zone 5 develops maximum speed and power.
What is VO2 max and how is it measured?
VO2 max is the maximum amount of oxygen your body can use during intense exercise, measured in mL/kg/min. It is the gold standard for aerobic fitness. Our calculator estimates VO2 max using the Cooper 12-minute run test or the Rockport walk test — no lab equipment required.
How can I use a pace calculator for race training?
A pace calculator helps you determine your per-mile or per-kilometer pace from a known distance and time. It also predicts finish times for common race distances (5K, 10K, half marathon, marathon) so you can set realistic goals and plan race-day pacing.