One-Rep Max (1RM) Calculator
Estimate your one-rep max from submaximal weight and reps. Free one-rep max (1rm) calculator for weightlifting, powerlifting, and gym programming.
Use this result well
- Inputs that matter
- Weight Lifted, Reps Completed
- Output to expect
- One-Rep Max (1RM) Calculator
- Check the units and required inputs before comparing results.
- Keep the assumptions with a copied result so you can reproduce the calculation later.
Related Tools
Tools you might need next
Estimate one-rep max bench, squat, and deadlift from submaximal sets. Free one rep max calculator using Epley and Brzycki formulas for strength training.
Calculate barbell plate loading for a target weight. Free plate loading calculator for weightlifting, powerlifting, and gym programming.
Plan weekly weight progression for a training block. Free progressive overload planner calculator for weightlifting, powerlifting, and gym programming.
Reference & details
How it works
Updated July 2026
How it works
Updated July 2026Formula Application & Mathematical Principles
This page shows the available inputs, calculation steps, and recorded method or source notes for One-Rep Max (1RM) Calculator. Source coverage varies by tool; independently confirm consequential results.
Standard Physical Constants & Reference Data
This page shows the available inputs, calculation steps, and recorded method or source notes for One-Rep Max (1RM) Calculator. Source coverage varies by tool; independently confirm consequential results.
Verification, Precision & Quality Control
This page shows the available inputs, calculation steps, and recorded method or source notes for One-Rep Max (1RM) Calculator. Source coverage varies by tool; independently confirm consequential results.
Updated: July 2026
Example Scenarios
Quickly convert measurements or calculate key metrics for laboratory data, coursework, homework, and scientific documentation.
Translate technical requirements between international standards and regional unit systems for field engineering project specs.
Verify technical data sheets, equipment specifications, and safety audit reports against standard unit guidelines.
Common Mistakes to Avoid
Common Mistakes to Avoid
Entering values in wrong units for One-Rep Max (1RM) Calculator
Check the expected unit for each input field (shown as suffix). Converting between imperial and metric units before entering values prevents calculation errors.
Dividing by zero or entering zero for a denominator field
Ensure denominator values (divisors) are non-zero. The calculator validates this, but understanding which fields cannot be zero helps interpret results correctly.
FAQ
About One-Rep Max (1RM) Calculator
The One-Rep Max (1RM) Calculator provides precise, instant unit conversions and calculations for professional, educational, and field applications. Designed for accurate results based on standardized physical and mathematical formulas.