One Rep Max Calculator
Estimate your 1RM and get a full training percentage table for any lift.
Estimated 1RM
90% (3–4 reps)
80% (6–8 reps)
70% (10–12 reps)
| % of 1RM | Weight | Rep Range | Training Zone |
|---|
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 good form. It's used to structure training percentages for strength, hypertrophy, and power programs.
Which formula is most accurate?▼
Epley is the most widely used. Brzycki is considered more accurate for lower rep sets (1–6). Mayhew performs better for higher rep sets (10+). No formula is perfectly accurate — treat your 1RM as an estimate.
How accurate are 1RM estimates?▼
Estimates are most accurate between 2–6 reps. Beyond 10 reps, accuracy drops significantly. The best way to know your 1RM is to test it with a spotter in a controlled environment.
How do I use 1RM percentages in training?▼
Use 90–95% for maximal strength (1–3 reps), 75–85% for hypertrophy (6–12 reps), 60–75% for muscular endurance (12–20 reps), and 30–60% for speed and power work. Most strength programs are written as percentages of 1RM.