buncha.tools
buncha/health & fitness/onerepmax

One Rep Max Calculator

Estimate your one-rep max from a recent set. Best with sets of 3–8 reps; less accurate above 10.
Weight lifted (kg)
Reps5
Estimated 1 rep max (average)
115.5 kg
from 100 kg × 5 reps
By formula
Epley
Most popular formula
116.5 kg
Brzycki
Common in powerlifting
112.5 kg
Lombardi
Gentler curve
117.5 kg
O'Conner
Conservative estimate
112.5 kg
Mayhew
Used in fitness research
119 kg
Training percentages
95%
Max effort
1–2 reps typical
110 kg
90%
Heavy strength
2–3 reps typical
104 kg
85%
Strength
4–5 reps typical
98.5 kg
80%
Strength + size
6–7 reps typical
92.5 kg
75%
Hypertrophy
8–9 reps typical
86.5 kg
70%
Hypertrophy / volume
10–12 reps typical
81 kg
65%
Endurance / volume
12–15 reps typical
75 kg
60%
Endurance
15+ reps typical
69.5 kg
Always warm up and use a spotter when training near your 1RM.

Pairs well with

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About One Rep Max Calculator

Calculate your 1RM from a working set. Five formulas, training percentage table.

Like every tool on Buncha, this one runs entirely in your browser. There's no upload, no log, no record of what you've pasted or generated. Close the tab and the data is gone.

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