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One-Rep Max Calculator

Enter one set's weight and reps to see your one-rep max and percentage table.

EpleyBrzycki2.5 kg rounding

Your details

How it is calculated

Your 1RM is the most you can lift for a single rep. Programs are written in percentages (5x5 at 80%), so you need it, but testing it for real is risky. Epley (weight × (1 + reps/30)) and Brzycki (weight × 36 / (37 − reps)) estimate it from a 2–10 rep set; the average of both is shown. Above 12 reps the estimate is unreliable.

The percentage table rounds to 2.5 kg (plate logic). FitCi estimates 1RM per exercise from your logs automatically and flags your PRs.

FitCi updates your 1RM every workout

Per-exercise 1RM from your sets, PR alerts and weight suggestions; on Apple Watch too.