These utilities are provided by Util Monster (util.monster) - util.monster
※ Based on Epley Formula (2025)
🎯 Purpose of this Calculator
Safely and accurately calculate your 1RM (One Rep Max), the most important metric in weight training. You can estimate your expected 1RM using only your current weight and repetitions without actually lifting maximum weight, and get appropriate training weights for different intensity levels.
Exercise
Weight Lifted
kg
Repetitions
reps
Estimated 1RM (One Rep Max)
Recommended Weight by Training Intensity
95% 1RM
1-2 reps (Max Strength)
90% 1RM
2-3 reps (Max Strength)
85% 1RM
4-6 reps (Strength)
80% 1RM
6-8 reps (Hypertrophy)
75% 1RM
8-10 reps (Hypertrophy)
70% 1RM
10-12 reps (Endurance)
65% 1RM
12-15 reps (Endurance)
60% 1RM
15+ reps (Warm-up)
※ Epley Formula: 1RM = Weight × (1 + Reps ÷ 30)
※ Accuracy is highest with 1-10 repetitions
※ Results may differ from actual 1RM with more than 10 reps
※ Always test actual 1RM safely with a spotter