About the One Rep Max Calculator
Estimate your 1RM from a set with several formulas (Epley, Brzycki, Lombardi) plus a full percentage table.
Also known as: 1rm calculator, max lift calculator, rep max calculator, estimated 1rm, rep-max.
How to use this calculator
- Enter weight lifted, reps completed, unit.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
One Rep Max formula
Epley: 1RM = w × (1 + reps/30) · Brzycki: w × 36/(37 − reps)
Worked example
Using the values pre-filled in the calculator above:
- Weight lifted = 100
- Reps completed = 5
- Unit: kg
the calculator returns:
- Estimated 1RM: 115.5 kg
- Epley: 116.7 kg
- Brzycki: 112.5 kg
- Lombardi: 117.5 kg