1RM Calculator
Discover your maximum strength for different exercises
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Fill in the fields above. It recalculates as you type.
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Understand 1RM
What is 1RM?
1RM (One Repetition Maximum) is the maximum weight you can lift in a single repetition of a specific exercise with perfect technique. It's the gold standard for measuring maximum strength and fundamental for intelligent training programming.
Plan Workouts
Use 1RM percentages to define ideal loads
Measure Progress
Track your strength evolution over time
Compare Strength
Compare relative strength between different exercises
Set Goals
Establish clear and measurable objectives
Training Zones by Percentage
Brzycki Formula
This is one of the most accurate formulas, especially for 1-10 repetitions
1RM = W ÷ (1.0278 − 0.0278 × reps)
How to use the calculator
Enter the weight you use for a specific exercise
Enter the number of repetitions you can perform with that weight
The calculator will estimate your 1RM using the Brzycki formula
Safety Tips
Warm-up
Always do a progressive warm-up before heavy loads
Perfect Technique
Maintain proper form even with maximum loads
Training Partner
Use a spotter when testing loads close to maximum
Periodization
Test 1RM maximum every 4-6 weeks
Popular Exercises for 1RM
Squat
King of leg exercises
Bench Press
Main chest exercise
Deadlift
Full body movement
Military Press
Shoulder strength
Row
Back development
Power Clean
Explosive power
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