🏋️ Fitness Calculator

One Rep Max Calculator

Estimate your 1RM (one repetition maximum) for any exercise using four proven formulas. Plus get your complete training weight chart by percentage.

Your Lift

Enter weight lifted and reps completed

Weight Lifted

Reps Completed

⚡ Quick Presets

Enter your lift details

Input the weight you lifted and the reps completed to estimate your 1RM.

Training by % of 1RM

Goal	% of 1RM / Reps
Max strength	90–100% / 1–3 reps
Strength	80–90% / 3–5 reps
Hypertrophy	67–85% / 6–12 reps
Endurance	50–67% / 12–20+ reps

Frequently Asked Questions

What is 1RM?

Your One Rep Max (1RM) is the maximum weight you can lift for a single repetition with proper form. It is the gold standard for measuring absolute strength.

Which formula is most accurate?

For reps ≤10, the Brzycki formula is generally considered the most accurate. For higher reps (10+), Epley or Lander may be more reliable. The average of all four provides a balanced estimate.

Should I test my actual 1RM?

For beginners and most recreational athletes, calculating 1RM from sub-maximal lifts is safer than actual testing. Only competitive powerlifters need to test true 1RM regularly.