ACTIVITY AND TRAINING ESTIMATES
Estimate one-repetition maximum strength from a lifted weight and repetitions using the Epley equation.
Your result
Enter your values and select Calculate. Your result stays on this device.
Epley estimate: 1RM = weight × (1 + repetitions ÷ 30).
Best suited to technically consistent submaximal sets. Exercise type, range of motion, fatigue, experience, equipment, and formula choice change the estimate.
This 1RM calculator gives lifters a planning estimate without requiring a true maximal attempt. The Epley method and an 80% reference load are shown explicitly.
Use case
Apply the Epley formula to entered weight and repetitions, show an 80% reference, and keep maximal-lifting safety limits explicit.
Estimate a one-repetition maximum from a technically consistent submaximal set.
Build a reliable scenario
One Rep Max Calculator helps you check a specific fitness & sports question with figures that apply to you. Estimate one-repetition maximum strength from a lifted weight and repetitions using the Epley equation. Apply the Epley formula to entered weight and repetitions, show an 80% reference, and keep maximal-lifting safety limits explicit. Estimate a one-repetition maximum from a technically consistent submaximal set. The page keeps the method and limits visible so the result can be understood, compared, and checked instead of treated as an unexplained answer.
Prepare Weight lifted and Completed repetitions. Enter the weight used for a technically consistent set. Enter completed repetitions from 1 through 30. Calculate the Epley one-rep-max estimate. Choose real training loads conservatively with qualified coaching and safe equipment. Keep units, dates, currency, and time periods consistent.
The stated method is: Epley estimate: 1RM = weight × (1 + repetitions ÷ 30). Change one assumption at a time to see which input drives the result, then compare scenarios on the same basis.
Best suited to technically consistent submaximal sets. Exercise type, range of motion, fatigue, experience, equipment, and formula choice change the estimate. Do not attempt an unsafe maximal lift from this estimate. Use appropriate supervision, technique, equipment, and medical clearance when needed.
Source and update
Last reviewed: 2026-08-22
National Strength and Conditioning Association — One-Repetition Maximum TestingIt is the greatest load a person can lift once with proper technique for a specific exercise.
No. Equations differ and individual performance depends on exercise, experience, fatigue, range of motion, and technique.
Not automatically. A maximal attempt has risks and should use appropriate preparation, supervision, equipment, and health judgment.
Keep exploring
Clear calculation guide
This free One Rep Max Calculator keeps the values and the calculation method visible instead of returning an unexplained number. Estimate one-repetition maximum strength from a lifted weight and repetitions using the Epley equation. Use it to check a scenario with the figures that apply to you.
Start by checking units, dates, decimal places, and the option you selected. This 1RM calculator gives lifters a planning estimate without requiring a true maximal attempt. The Epley method and an 80% reference load are shown explicitly. The stated mathematical method is: Epley estimate: 1RM = weight × (1 + repetitions ÷ 30).
Change one assumption at a time to understand what moves the result, then keep any final record or institution-specific rule separate from the arithmetic. Best suited to technically consistent submaximal sets. Exercise type, range of motion, fatigue, experience, equipment, and formula choice change the estimate. Hesaplayın is a clear, browser-based calculator for checking the maths behind your decision.