1RM Calculator

Calculate your One-Rep Max (1RM) and get personalized training recommendations.

Metric (kg) Imperial (lb)

Exercise

Your Estimated One-Rep Max

0

kg

1RM Estimates by Formula

Brzycki Formula 0

Epley Formula 0

Lombardi Formula 0

Mayhew Formula 0

Training Zones

Strength (85-100% of 1RM)

1-5 reps per set
3-5 minutes rest between sets
Focus on maximal strength development

Hypertrophy (70-85% of 1RM)

6-12 reps per set
1-2 minutes rest between sets
Focus on muscle growth

Endurance (60-70% of 1RM)

12+ reps per set
30-60 seconds rest between sets
Focus on muscular endurance

Exercise-Specific Recommendations

About 1RM Calculator

Our 1RM Calculator helps you estimate your One-Rep Max (1RM) - the maximum weight you can lift for a single repetition.

1RM Formulas

Brzycki Formula: Weight × (36 / (37 - reps))
Epley Formula: Weight × (1 + 0.033 × reps)
Lombardi Formula: Weight × reps^0.1
Mayhew Formula: (100 × Weight) / (52.2 + 41.9 × e^(-0.055 × reps))

Training Zones

Strength: 85-100% of 1RM, 1-5 reps
Hypertrophy: 70-85% of 1RM, 6-12 reps
Endurance: 60-70% of 1RM, 12+ reps

Important Notes

1RM estimates are approximations and may vary based on individual factors
Always use proper form and technique
Consider working with a qualified trainer for proper guidance
Progress gradually to avoid injury
Not suitable for beginners or those with health conditions