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.

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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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