Train smarter, not just harder
Strength, running and heart-rate calculators that turn your workouts into clear numbers and targets.
🏋️ Strength
One Rep Max Calculator
Estimate your one-rep max from a weight and the number of reps you can lift, using the Epley and Brzycki formulas.
Lifting Percentage Calculator
Turn your one-rep max into a percentage chart (50–100%) with the weight and approximate reps for each percentage.
Training Volume Calculator
Calculate total training volume (tonnage) for up to three exercises from sets, reps and weight, to track progressive overload.
🏃 Running & Walking
Running Pace Calculator
Calculate your running pace per mile and per kilometer, and your average speed, from distance and finish time.
Race Time Predictor
Predict your finish time for other race distances from a recent race result, using the Riegel formula.
VO2 Max Calculator
Estimate your VO2 max (aerobic fitness) from the distance you can run in 12 minutes, using the Cooper test formula.
Steps to Miles Calculator
Convert steps to miles and kilometers using a stride length estimated from your height, or your own measured stride.
❤️ Heart & Energy
Target Heart Rate Calculator
Find your maximum heart rate and target heart rate training zones from your age and resting pulse, using the Karvonen heart rate reserve method.
Calories Burned Calculator
Estimate calories burned walking, running, cycling, swimming, lifting, yoga and more, from your weight and workout length.
Frequently Asked Questions
Do I need to sign up or log in?
No. Every calculator works instantly without an account. A free account is only needed if you want to save results (up to 30) and see them later.
Is my data stored anywhere?
The numbers and dates you type are calculated in your browser and are not sent to us. We keep basic visit statistics (page visited, IP address, browser, time) and, if you save a result, that saved result in your account. The AI Assistant sends your question to an AI provider to answer it.
Are the results exact?
Date and age maths is exact. Money, tax and health tools are estimates based on published formulas and official tables, and are not professional advice.