Use this Rep Max Calculator to work out your working weight for different rep targets. Enter the weight you lifted and how many reps you achieved (for example, your 5RM), and the calculator will estimate what weight you should use for another rep range—like 12 reps—so you can choose the right load for your session.
For best results, use a weight you can lift for 1–20 reps with good form. The calculator uses established strength formulas to estimate equivalent weights across rep ranges; see the Estimation methods section for how the calculations are done.
Modify the values and click the Calculate button to use
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