About RepMaxLab

RepMaxLab is a small set of free calculators for strength athletes — built to be accurate, fast and honest about how the numbers are produced.

What we make

Every tool on this site answers one question lifters actually ask in the gym:

One Rep Max Calculator

Estimate your 1RM from any set using six established formulas, with a percentage table and training max.

DOTS Calculator

The powerlifting score used by USAPL and IPF affiliates to compare totals across bodyweights.

Strength Standards

See whether your squat, bench, deadlift and overhead press are beginner, intermediate, advanced or elite for your size.

RPE Calculator

Estimate your max from a set rated by effort, and find working weights for any reps and RPE.

Wilks Calculator

The classic powerlifting score, calculated with the original published coefficients.

How the numbers are calculated

We do not invent formulas. The 1RM estimates use published equations (Epley, Brzycki, Lombardi, Mayhew, O'Conner and Wathan) and show all of them side by side, because no single formula is best for every lifter. The DOTS and Wilks calculators use the official published coefficients — the same values used in competition software — and the RPE tool uses the standard RPE-to-percentage chart used across powerlifting. Where a number is an approximation (like the strength-standards tables), the page says so.

Privacy by design

All calculations run in your browser. There are no accounts, nothing you type is sent to a server, and we store nothing about your lifts. Read the full privacy policy for details.

Contact

Found a wrong number or have a suggestion? Reach us through the contact page.