How to Use Your 1RM

The Epley Formula

1RM = Weight × (1 + Reps/30). This is the most widely used formula and most accurate for 3–12 rep ranges. Results become less reliable above 12 reps.

Training Percentage Zones

60–70% of 1RM: endurance and technique work (12–20 reps). 70–80%: hypertrophy zone (8–12 reps). 80–90%: strength zone (3–6 reps). 90–100%: maximum strength (1–3 reps).

Safety Note

Do not test your actual 1RM without proper warm-up, spotters, and experience. Most programs use calculated 1RM from submaximal lifts to set training weights safely.

One Rep Max Calculator

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