One-Rep Max Calculator
Estimate your max lift from a lighter set.
Your result
Estimates are most accurate for sets of 10 reps or fewer. Test true maxes only with a spotter.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Find this tool when you want to:
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Frequently asked questions
What does the One-Rep Max Calculator do?
Estimate your max lift from a lighter set. Enter your values and the result and chart update instantly.
How accurate is it?
It uses published, widely used formulas. Results are estimates for education and planning, not a diagnosis. Talk to a qualified clinician about decisions affecting your health.
Is my information stored or shared?
No. All calculations run in your browser and nothing you type is sent to a server or saved.
What can I search to find this tool?
People find it by searching for: how much can i lift; bench press max; strength training percentages; squat max.