About
PowerliftMath
Free calculators for powerlifters, plus a paid plan that adjusts to how training goes. This page explains where the numbers come from and how we check them.
How the numbers are made
Every score uses the published constants, not a fitted guess. DOTS and Wilks 2020 match the coefficients in the OpenPowerlifting database; IPF GL matches the IPF’s own 2020 coefficient table. Each calculator page lists its sources at the bottom, with the date they were last checked.
Program calculators (Smolov Jr, 5/3/1, the beginner linear plan) follow the standard percentages for each program and round every set to a weight you can actually load with competition plates.
The adaptive plan is a fixed set of rules, not an AI: percentages of your estimated max, RPE targets and a phase per week, adjusted by at most ±10% over a block from your feedback. The same inputs always give the same plan, so you can check the math.
How we test it
The formulas and the plan engine have automated tests that run before each release: the published worked example for each score formula, spot checks against the RTS RPE chart, plate loading at awkward weights, and adaptive plans that must stay inside their ±10% cap whatever feedback comes in. Sources were last reviewed on .
What this site is not
It is not medical advice or a substitute for a coach who can watch you lift. Percentages are averages; your own numbers may run a little high or low. If something hurts, stop and see a professional.
Found a wrong number?
Email support@powerliftmath.com with the page, what you entered and what you expected. We check every report against the source and fix confirmed errors, usually within a few days.
Questions about a paid plan, a refund or your data go to the same address. See the privacy policy and terms for the details.