Toolwright

Free online 1rm calculator

One Rep Max Calculator

One-rep max calculator using the Epley formula, plus training percentages.

  • Free · No signup
  • Instant results
  • Private in your browser
  • Works on mobile

Result

Estimate one-rep max from a submaximal set (Epley).

About this 1rm calculator

Estimate your 1RM from a submaximal set and see common training percentages (65–95%) for programming.

Use this free online one rep max calculator when you need a quick, clear estimate without creating an account. Calculations run in your browser on Toolwright, so your inputs stay private. Results are for education and planning — confirm important financial, tax, or health decisions with a qualified professional.

How to use the One Rep Max Calculator

  1. Enter the values asked for in the form — amounts, rates, dates, or measurements depending on the tool.
  2. Tap calculate to see your result instantly. Adjust inputs anytime to compare scenarios.
  3. Review the breakdown and FAQs below if you want more context on what the numbers mean.

Why people use Toolwright

  • Clear answers — dedicated page for the one rep max calculator, built to load fast and stay easy to read.
  • Fast & free — no paywall, no email gate, results above the noise.
  • US-ready — copy and units aimed at American and Western users.
  • One toolkit — jump to related fitness & health tools without leaving the site.

One Rep Max Calculator FAQ

Which formula is used?

Epley: weight × (1 + reps/30). Best for roughly 1–10 reps.