What is a one rep max (1RM)?

Your one rep max is the maximum weight you can lift for a single repetition with proper form. It is used to program training intensity as a percentage of 1RM.

How accurate is the 1RM estimate?

The Epley formula is most accurate with 2-10 reps. Above 10 reps, estimates become less reliable. For best accuracy, use a weight you can lift for 3-5 reps.

What percentage of 1RM should I train at?

Strength: 85-100% (1-5 reps). Hypertrophy: 67-85% (6-12 reps). Endurance: 50-67% (12-20 reps). Warm-up: 40-60%.

Should I test my actual 1RM?

Direct 1RM testing carries injury risk. Estimating from submaximal sets is safer and nearly as accurate. Only test directly with a spotter and proper warm-up.

One Rep Max Calculator

Estimate your one-rep max (1RM) from weight lifted and reps completed. See training percentages.

Weight Lifted

lbs

Reps Completed

Estimated 1RM

—

95% (2 reps) —

90% (3-4 reps) —

80% (7-8 reps) —

70% (12-15 reps) —

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Weight Lifted

lbs

Reps Completed

Formula

Estimated 1RM

—

90% (3-4 reps) —

80% (7-8 reps) —

70% (12-15 reps) —

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Weight Lifted (lbs)

Reps Completed

Body Weight (lbs)

Age

Gender

Years Training

Lift

1RM Estimates

1RM (Epley) —

1RM (Brzycki) —

1RM (Lander) —

Average 1RM Estimate —

Training Percentages

95% 1RM (2 reps) —

90% 1RM (3-4 reps) —

85% 1RM (5-6 reps) —

80% 1RM (7-8 reps) —

75% 1RM (10 reps) —

70% 1RM (12 reps) —

Strength Assessment

Strength/Bodyweight Ratio —

Strength Level —

How to Use This Calculator

Enter the weight you lifted and how many reps you completed. The calculator estimates your one-rep max using the Epley formula and shows training weights at various percentages.

Formula

Epley Formula: 1RM = Weight × (1 + Reps / 30)

Training percentages: 95% (2 reps) | 90% (3-4 reps) | 80% (7-8 reps) | 70% (12-15 reps)

Example

Example: Bench press 185 lbs for 5 reps: 1RM = 185 × (1 + 5/30) = 216 lbs. Train at 80% = 173 lbs for 7-8 reps.

Frequently Asked Questions

Your one rep max is the maximum weight you can lift for a single repetition with proper form. It is used to program training intensity as a percentage of 1RM.
The Epley formula is most accurate with 2-10 reps. Above 10 reps, estimates become less reliable. For best accuracy, use a weight you can lift for 3-5 reps.
Strength: 85-100% (1-5 reps). Hypertrophy: 67-85% (6-12 reps). Endurance: 50-67% (12-20 reps). Warm-up: 40-60%.
Direct 1RM testing carries injury risk. Estimating from submaximal sets is safer and nearly as accurate. Only test directly with a spotter and proper warm-up.

Related Calculators

Sources & References (5) ▾