Training
One Rep Max Calculator
Estimate your one-rep max and training percentages from a weight you can lift for multiple reps.
Your result will appear here
Enter a lift and reps to estimate your one-rep max.
Calculator guide
How to understand your one-rep max result
How to use this calculator
- 1Enter the weight you lifted.
- 2Enter how many reps you completed with that weight.
- 3Click the calculate button to estimate your one-rep max.
- 4Review the training percentage table for estimated working weights.
What the result means
The one-rep max result estimates the maximum weight you may be able to lift for one repetition. The percentage table can help estimate training loads, but real performance can vary based on exercise type, technique, fatigue and recovery.
This calculator is for informational purposes only. Do not attempt maximum lifts without proper technique, preparation and safety.
What is one-rep max?
One-rep max, or 1RM, is an estimate of the maximum weight you may be able to lift for one complete repetition. This calculator uses a common estimation formula based on a submaximal lift.
Formula used: 1RM = weight × (1 + reps / 30)
This calculator is for informational purposes only. Train safely and avoid max attempts without proper preparation.
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