Health Calculators

One-rep max.

Estimate your 1RM from any sub-maximal set using the Epley formula. We hand back a full training-percentage table so you can program by intensity, not feel.

Your lift

kg
Use 3-5 reps for most accurate results.

Estimated 1RM

Fill the form and press Calculate.

How the 1RM calculator works

This calculator uses the Epley formula: 1RM = Weight x (1 + 0.0333 x Reps). It is most accurate at 3-5 reps and degrades beyond 10 reps as muscular endurance starts to dominate.

Using the percentage table

90-100% (1-3 reps): max strength. 80-90% (3-6 reps): strength. 70-80% (6-12 reps): hypertrophy. 60-70% (12-20 reps): endurance and conditioning. 50-60%: speed and power work.

Disclaimer

Educational estimate only. Never attempt weights beyond your trained capability. Warm up thoroughly, use proper form, and have spotters or safety equipment for heavy lifts.