Using percentages to program
Once you have a working 1RM, most strength programs assign loads as percentages. Linear progressions live at 75–85%, peaking blocks push 90%+, and technique or speed work sits at 50–65% moved fast.
- • Recalculate every 4–6 weeks or after any rep PR.
- • Use a training max of 90% of the estimate to leave room on bad days.
- • Never test a true 1RM without a spotter and a full warm-up ramp.
FAQ
How accurate are 1RM calculators?
Within about 5% when the input set is 3–6 hard reps. Accuracy falls off quickly above 10 reps and for lifters new to maximal effort.
Which 1RM formula is best?
Epley and Brzycki are the most widely used and agree closely under 8 reps. Averaging several formulas, as this tool does, smooths out their individual bias.
Should I actually test my one rep max?
Occasionally, if you compete. For general training, estimated maxes from a hard set of 3–5 give you everything you need without the recovery cost.
How this calculator is built
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Written by Sam Doshi and the RevenueLab editorial team. We don't sell the data feeds this tool is built on.
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