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Sync settings

Choose what your account keeps in step on every device where you are signed in.

  • My tools

    Always synced: the tools on your board, their order and size.

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One Rep Max Calculator

Estimate a one-repetition maximum from the weight and repetitions completed.

My tools →

Epley estimate

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Brzycki estimate

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Estimated maximum only. Use a spotter and safe lifting technique.

Runs in your browser – your data never leaves your device Also available via our free API

How to use the One Rep Max Calculator

  1. 1 Enter the requested details.
  2. 2 Review the estimate and the limitations shown with it.

How the estimate works

This calculator shows estimates from the Epley and Brzycki equations. Both use a submaximal set to estimate the heaviest load you might lift once. Formula estimates can differ and are less reliable at higher repetition counts. Do not attempt a maximal lift without appropriate experience and safe conditions.

How to use this calculator

Enter the requested values and review the result alongside the limits of the estimate.

Important limitations

This result is for general information. Individual circumstances can change what is appropriate; consult a qualified professional when making health decisions.

Frequently asked questions

How does this calculator work?

This calculator shows estimates from the Epley and Brzycki equations. Both use a submaximal set to estimate the heaviest load you might lift once. Formula estimates can differ and are less reliable at higher repetition counts. Do not attempt a maximal lift without appropriate experience and safe conditions.

Is this a diagnosis or personalized advice?

No. This is an informational estimate and does not replace professional advice.

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