1RM Calculator

Estimate your one-rep max based on the weight and reps you can perform.

Your Lift

kg
reps

Best accuracy with 1-10 reps

Your Estimated 1RM

115

kg

Based on 100kg × 5 reps

Training Zones

Strength

85-100% (1-5 reps)

98-115kg

Hypertrophy

65-85% (6-12 reps)

75-98kg

Endurance

50-65% (12-20+ reps)

58-75kg

Track Your Lifts

Record your PRs in Tormel

Percentage Chart

% of 1RMWeightRep Range
100%115kg1 reps
95%109kg2 reps
90%104kg3-4 reps
85%98kg5-6 reps
80%92kg7-8 reps
75%86kg9-10 reps
70%81kg11-12 reps
65%75kg13-15 reps
60%69kg15-20 reps

What is 1RM?

One-Rep Max (1RM) is the maximum weight you can lift for a single repetition with proper form. It's used to gauge strength and calculate training weights.

How to Use

Use your 1RM to program training. For strength, work at 80-95%. For muscle growth (hypertrophy), use 65-80%. For endurance, stay at 50-65%.

Safety Note

This is an estimate. Actual 1RM testing should be done with a spotter or in a power rack. Accuracy decreases with reps above 10.