PT

1RM Calculator

Estimate your one-rep max from any weight and rep count using the Brzycki formula.

Estimated 1RM

113 kg

Percentage Chart

100% — ~1 reps 113 kg
95% — ~2 reps 107 kg
90% — ~3 reps 102 kg
85% — ~5 reps 96 kg
80% — ~6 reps 90 kg
75% — ~8 reps 85 kg
70% — ~10 reps 79 kg
65% — ~12 reps 73 kg
60% — ~15 reps 68 kg

What is a 1RM?

Your one-rep max (1RM) is the maximum weight you can lift for a single repetition with proper form. It's the gold standard for measuring strength and is used to programme training percentages.

How to use your 1RM

Most training programmes prescribe weights as a percentage of your 1RM. For example, "5x5 at 80%" means 5 sets of 5 reps at 80% of your one-rep max. The percentage chart above gives you these numbers instantly.

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