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Strength

1RM (One Rep Max)

Estimate your maximum one-rep weight and get your complete training intensity table.

What is 1RM?

The 1RM (one repetition maximum) is the maximum weight you can lift in an exercise for a single repetition with correct technique. It is the standard reference for prescribing strength training intensities.

How is it estimated?

Three validated formulas are used: Epley (1985), Brzycki (1993) and Lander (1985), and the results are averaged for greater precision. The estimate is most accurate with 2–6 repetitions.

Formula

Epley: 1RM = weight × (1 + reps/30) · Brzycki: 1RM = weight / (1.0278 − 0.0278 × reps)

⚠️ Limitations

Accuracy decreases with more than 10 repetitions. Always work with a spotter when lifting close to true maximum.

FAQ

Not necessary. Formulas with 3–5 reps give very reliable results and are safer.
For maximal strength: 85–95% of 1RM in sets of 1–3 repetitions.
70–85% of 1RM in sets of 6–12 repetitions is the most effective range.
Every 4–8 weeks, or when training weight feels too easy.