Nine running and fitness calculators, one owner, and math you can check by hand.
ExerciseCalc exists because most runners do not want to carry a spreadsheet on race day. The site is nine calculators built around the handful of numbers that actually matter for training and racing: pace, calories burned, heart-rate zones, aerobic fitness, and the conversion between steps and distance. Enter a distance, a time, a weight or an age, and the tool does the arithmetic instantly, in your browser, with no sign-up.
Nothing here is a black box. Every calculator uses a formula that has been published somewhere for years, sometimes decades: the MET method for calorie burn, Riegel's exponential formula for predicting a race time at a new distance, the Karvonen or age-based method for heart-rate zones, the Cooper 12-minute test for aerobic fitness. The editorial standards page names exactly which formula backs which tool and where it comes from.
ExerciseCalc is owned and operated by Chris Terry through Encore Promotional Products, one of a small set of free calculator sites in the Encore Editorial network. Chris built the calculators and sets the sourcing standard on the editorial standards page. The pace, calorie and training guides are written by Naomi Foster; neither of them is a coach or a clinician, and the authors page spells out exactly what gets checked, by whom, before a guide goes up.
It is not a coaching service, a training-log app, or a substitute for a doctor's clearance before starting a new exercise program. There is no account, no saved history, and no personal training plan generated from your inputs; every result is a one-time calculation based on the numbers you enter that session. If you want ongoing coaching or a medical opinion on your training, that has to come from a person qualified to give it, not a calculator.
ExerciseCalc is free because it carries Google AdSense advertising and a small number of affiliate links; if you click one and buy something, we may earn a commission at no extra cost to you. That revenue never changes which formula a calculator uses or what number it returns.