One Rep Max Calculator
Enter weight and reps to estimate 1RM using common formulas.
Epley: 1RM = w * (1 + r/30). Brzycki: 1RM = w * 36/(37-r). Lombardi: 1RM = w * r^0.10
60 kg * 8 reps -> Epley ~= 76 kg (example).
Which 1RM formula should I pick?
Epley, Brzycki, and Lombardi are common estimators for 1–10 reps. Differences are usually small in that range.
Is the estimate valid for high reps?
Accuracy drops as reps increase. For >10 reps, use caution; these formulas extrapolate from submax sets.
Should I warm up before testing?
Yes. Use proper warm‑ups and safe technique. Never test when fatigued or injured.
Can I convert kg to lb?
Yes. Enter your preferred unit; 1 kg ~= 2.20462 lb for conversions if needed.
Which formula is best?
Epley and Brzycki are common. Differences are small for 1–10 reps; choose the one you prefer.
📐 Formula
Epley: 1RM = w * (1 + r/30). Brzycki: 1RM = w * 36/(37-r). Lombardi: 1RM = w * r^0.10
📝 Example Calculation
60 kg * 8 reps -> Epley ~= 76 kg (example).
❓ Frequently Asked Questions
Which 1RM formula should I pick?▼
Epley, Brzycki, and Lombardi are common estimators for 1–10 reps. Differences are usually small in that range.
Is the estimate valid for high reps?▼
Accuracy drops as reps increase. For >10 reps, use caution; these formulas extrapolate from submax sets.
Should I warm up before testing?▼
Yes. Use proper warm‑ups and safe technique. Never test when fatigued or injured.
Can I convert kg to lb?▼
Yes. Enter your preferred unit; 1 kg ~= 2.20462 lb for conversions if needed.
Which formula is best?▼
Epley and Brzycki are common. Differences are small for 1–10 reps; choose the one you prefer.