1RM (one-rep max) is the maximum weight you can lift for one repetition with proper form. Trainers often estimate it from submaximal sets to program strength training safely.

Which 1RM formula should I use?

Epley is widely used for general strength training. Brzycki is popular for lower rep ranges. Lombardi can work well for higher reps. Use the same formula consistently to track progress.

Gym 1RM Calculator

Estimate your one-rep max from a submaximal set. Includes training percentages for programming.

Weight unit

Kilograms (kg) Pounds (lbs)

Weight lifted

Reps completed

Best for 2–10 reps. At 1 rep, lifted weight equals your 1RM.

Formula

Estimate only. Always use a spotter and proper form when testing heavy lifts.

Example: Lifting 100 kg for 5 reps (Epley) gives an estimated 1RM of 116.7 kg.

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