1RM Calculator
Enter the weight lifted and reps performed to see your predicted 1RM. For a relative score, be sure to also enter your bodyweight
One Rep Max Calculator (1RM Calc)
Estimate and predict your 1RM with easy to use calculator. Utilising seven different and proven formulae for measuring your one rep max from a single trainingset.
Pro tip: Save this web page to your phone home screen for quick access during your future workouts!
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Metric VBT automatically calculates your 1RM from bar speed data, along with bar path tracking, RPE logging and a full workout builder.
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How to use the 1RM calculator
This online calculator, uses seven (7) different scientifically validated 1RM estimation formulae to deliver you an accurate estimation of your maximum strength levels for bench press, back squat, deadlift or any other standard barbell strength movement.
Whether you're a beginner or seasoned athlete, the 1RM calculator isa great tool to help you accurately predict your strength levels and optimise your training. As a way to measure your 1RM without actually performing a one rep max, simply enter the weight and reps performed for any set taken to failure, the online calculator will automatically generate your estimated 1RM for that exercise in absolute terms and relative to bodyweight.
For best results - use data from a set between 2 and 10 reps. This one rep max strength calculator work for most barbell strength exercises; bench press, back squat, front squat, deadlift, trapbar deadlift, overhead press and more.
1RM estimation with this calculator is less effective on Olympic movements such as the Clean and Snatch.
Most accurate max strength calculator
There are a number of scientifically validated formula for estimating your one rep max. Some are exercise specific, others more general.
Instead of choosing just one, this calculator runs your lifting data through seven of the most popular scientifically validated formulas to provide an averaged 1RM prediction along with the outputs for each of the unique 1RM formulas for comparison.
Always be sure to perform a maximum sets with a spotter present and use proper equipment to ensure safety.
Alternative methods to calculate your one rep max
The rep-max approach to estimating your 1RM is not the only way to find your strength levels.
On this site, you will find a number of calculators and training tools that allow you to measure your strength in the gym from submaximal training data. Two of my favourites are to perform a submaximal set and then RPE to 1RM conversion calculator or generating a load-velocity profile from the data produced with a barbell velocity tracker app like Metric VBT. Both are accurate methods and do not require a maximal effort set, using data from regular training data only.
Finally, if you really want to know your 1RM, this 1RM warmup calculator provides a detailed guide and load suggestions for you to perform the perfect loading ramp before attempting your 1RM test.
Further reading about 1RM calculations
A lifters guide to 1RM strength testing →