One Rep Max Calculator

Estimate your 1RM using multiple proven formulas

Formula

Multiple formulas: Epley: W×(1+R/30), Brzycki: W×36/(37-R), Lander: W×100/(101.3-2.67R), Lombardi: W×R^0.10, etc. Average provides best estimate.

All formulas estimate 1RM from submaximal reps. They differ in assumptions about the force-velocity relationship. Averaging reduces individual formula bias.

How to Calculate Manually

1
Enter the weight you lifted
2
Enter how many reps you completed
3
Select lbs or kg
4
Calculator shows 1RM from 7 formulas + average
5
Training percentages shown for program design

Reference Table

Reps	% of 1RM (approx)	Typical Use
1	100%	Max testing
2	95%	Power
3	93%	Strength
4	90%	Strength
5	87%	Strength
6	85%	Strength/Hypertrophy
8	80%	Hypertrophy
10	75%	Hypertrophy
12	70%	Hypertrophy/Endurance
15	65%	Endurance
20	60%	Endurance

One Rep Max Calculator: Estimate Your 1RM for Bench, Squat, Deadlift

The one-repetition maximum (1RM) is the gold standard for measuring absolute strength. It represents the maximum weight you can lift for a single repetition with proper form. While testing your true 1RM has its place, it carries injury risk and requires significant recovery. Estimation formulas allow you to gauge your max strength from safer submaximal sets...

Frequently Asked Questions

What is a 1RM? One-repetition maximum (1RM) is the maximum weight you can lift for exactly one repetition with proper form. It's the standard measure of absolute strength.: One-repetition maximum (1RM) is the maximum weight you can lift for exactly one repetition with proper form. It's the standard measure of absolute strength.
Which formula is most accurate? Epley is most popular. Brzycki works well for higher reps (8-12). For best estimate, use multiple formulas and average. True 1RM can only be found by testing.: Epley is most popular. Brzycki works well for higher reps (8-12). For best estimate, use multiple formulas and average. True 1RM can only be found by testing.
Is estimating 1RM safe? Yes, estimating from submaximal sets (3-10 reps) is much safer than attempting a true 1RM. Always use a spotter for heavy lifts.: Yes, estimating from submaximal sets (3-10 reps) is much safer than attempting a true 1RM. Always use a spotter for heavy lifts.

Calculator

Formula

Formula

How to Calculate Manually

Reference Table

One Rep Max Calculator: Estimate Your 1RM for Bench, Squat, Deadlift

Frequently Asked Questions

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