Enter a weight and rep count from a recent set to estimate your true one-rep max — for bench press, squat, deadlift, or any barbell lift.
Use these to plan working sets once you know your 1RM.
| % of 1RM | Weight | Typical use |
|---|
1RM = weight × (1 + reps ÷ 30). The most widely used formula, reliable in the 2–10 rep range. Good default for most lifters.
1RM = weight × 36 ÷ (37 − reps). Slightly more conservative than Epley, especially past 8–10 reps. Favored by some coaches for moderate rep ranges.
1RM = weight × reps^0.10. Tends to run higher at low rep counts. Useful as a cross-check rather than a primary number.
Estimates are most reliable using a set of 1–5 reps taken close to failure. Above 10 reps, all formulas lose accuracy — treat the number as a planning tool, not a guarantee.
Not without a spotter and a proper warm-up progression. Most lifters use the estimate to set training percentages rather than to attempt a true 1RM in every session.