One Rep Max Calculator
Calculate your one rep max (1RM) using 5 proven formulas — then get a full training table with weights for every intensity level
Your Lift
Best accuracy at 1–10 reps
Enter weight and reps to calculate your 1RM
Formula Breakdown
Results from 5 formulas will appear here
1RM estimates are most accurate at 1–10 reps. Accuracy decreases at higher rep counts. Always warm up properly and train safely.
Frequently asked questions
What is a one-rep max (1RM)?
Your 1RM is the maximum weight you can lift for exactly one full repetition with proper form. It's the gold standard for measuring absolute strength in exercises like the squat, bench press, and deadlift.
Which 1RM formula is most accurate?
The Epley and Brzycki formulas are the most widely used and validated. All five formulas are most accurate at low rep counts (1–10 reps). As reps increase beyond 10, estimates become less reliable.
How do I use my 1RM for programming?
Multiply your estimated 1RM by a training percentage: use 85–95% for heavy strength work (1–5 reps), 70–80% for moderate hypertrophy (6–12 reps), and 50–65% for lighter volume work.
Should I test my 1RM directly?
Direct 1RM testing carries injury risk, especially for beginners. Estimating from a 3–5 rep set is safer and can be nearly as accurate. Always warm up thoroughly before any max effort.