Estimate your one-rep max from a submaximal lift using four validated formulas. Calculate training percentages for effective strength programming.
Last updated: March 2026
Disclaimer: This calculator provides estimated 1RM values using four validated formulas. It is for training and informational purposes only.
Estimated 1RM values vary based on individual factors including training history, equipment, form, fatigue level, and individual response to different rep ranges. Use these estimates as guidance for training loads, not as absolute measures. Always prioritize proper form and safety. For medical concerns or injuries, consult a healthcare professional.
Epley
116.666667 kg
Brzycki
112.5 kg
Lander
113.708918 kg
Lombardi
117.461894 kg
Average 1RM
115.08437 kg
Training Percentages (Based on Average)
95%
109.330152 kg
90%
103.575933 kg
85%
97.821715 kg
80%
92.067496 kg
75%
86.313278 kg
70%
80.559059 kg
65%
74.804841 kg
60%
69.050622 kg
Your one-rep max (1RM) is the maximum amount of weight you can lift for a single repetition of a given exercise with proper form. It's a fundamental metric in strength training used to measure absolute strength and program training loads.
Rather than testing your 1RM directly (which carries injury risk and requires maximal effort), you can estimate it from a submaximal lift. If you can lift a certain weight for multiple reps, mathematical formulas can predict your theoretical 1RM. This approach is safer and can be done during regular training.
Multiple formulas exist because the relationship between reps and max weight varies slightly between individuals, exercises, and training backgrounds. Using multiple formulas and averaging them provides a more robust estimate.
Most accurate for 1-10 reps. Accuracy decreases above 10 reps.
Estimate 1RM from lifting 100 kg for 5 reps:
Your estimated 1RM is about 115 kg.
Epley and Brzycki are most commonly used and validated. Epley tends to be more accurate for lower reps (1-5), while Brzycki works better for higher reps (6-10). Using the average of all formulas provides the most robust estimate.
Testing true 1RM carries higher injury risk and requires complete freshness, proper warm-up, and ideally a spotter. For most training purposes, estimated 1RM is sufficient and safer. Reserve max testing for competitions or specific program milestones.
Formulas are most accurate for 1-10 reps, with peak accuracy at 3-5 reps. Above 10 reps, muscular endurance becomes a larger factor and estimates become less reliable. For best results, use a weight you can lift 3-8 times.
Training percentages guide load selection: 60-70% for volume/hypertrophy, 70-85% for strength, 85-95% for max strength, 95%+ for peaking. For example, if your 1RM is 100 kg, use 70-85 kg for strength-focused sets.
Retest every 4-8 weeks to track progress, or when you notice significant strength changes. More frequent testing can interfere with training. Progressive overload in your regular training will naturally increase your 1RM over time.
These formulas work best for compound movements (squat, bench, deadlift, overhead press). They're less accurate for isolation exercises, bodyweight movements, or exercises limited by factors other than raw strength (balance, coordination, etc.).
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