Question 1

What is a One Rep Max Calculator?

Accepted Answer

The one-repetition maximum (1RM) is the maximum weight you can lift for a single repetition of an exercise with good form. It is the gold standard for measuring strength and is used to calculate training percentages. Because testing true 1RM carries injury risk, estimation formulas from submaximal efforts are commonly used.

References

Question 2

How does the One Rep Max Calculator work?

Accepted Answer

Epley (1985): 1RM = weight × (1 + reps/30) Then: Brzycki (1993): 1RM = weight × 36 / (37 − reps) Then: Both formulas are most accurate for 3–10 reps; less accurate above 12 Then: Training percentages are calculated as % of 1RM for different adaptations.

Question 3

Can you give an example of how to use the One Rep Max Calculator?

Accepted Answer

Example: Input 80kg for 5 reps (Epley) gives a result of 1RM ≈ 93.3 kg (80 × (1 + 5/30) = 93.3).

Question 4

Is the One Rep Max Calculator free to use?

Accepted Answer

Yes — completely free with no registration, download, or subscription required. All calculations happen instantly in your browser.

Question 5

How accurate is the One Rep Max Calculator?

Accepted Answer

Our One Rep Max Calculator uses verified mathematical formulas and is accurate to multiple decimal places. Results are calculated in real-time using the same methods used by professionals.

One Rep Max Calculator

One Rep Max Calculator

What is One Rep Max Calculator?

How to Use One Rep Max Calculator

Example One Rep Max Calculator

Training Percentage Guide

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