The site

About

OneRepMax is a free calculator for a one-rep max. You enter a weight and the reps you lifted. The page estimates a 1RM with seven published formulas, then turns that estimate into a percentage chart in kilograms or pounds.

The other tools answer narrower questions: a bench chart, an RPE percent, DOTS, Wilks, the plates on one side of a bar, a training max, FFMI, a field estimate of VO2, heart-rate bands. Guides explain how to use the numbers without pretending a formula watched your set.

What this site does not do

It does not coach you. It does not sell a program. It does not give medical advice. It does not store an account, and the history of what you typed stays in your browser. A byline from Jacob Young, Editor, is an editorial credit, not a medical review and not a certification.

Questions and corrections go to support@onerepmax.io. The rules for sources and corrections are on the editorial standards page.