AtlasCalc🏋️ FitnessbeginnerOffline
One-Rep Max
Estimated 1-rep max from submaximal lifts.
Inputs
Enter your values below.
Result
Your answer appears here.
Enter values and press Calculate — the result appears here.
How it works
The formula behind this calculator.
Epley: 1RM = w × (1 + r/30); Brzycki: 1RM = w / (1.0278 − 0.0278r)
- w
- Weight lifted
- r
- Number of reps performed (must be < 10)
These formulas estimate your 1RM from a submaximal set. The two diverge as reps climb. They're most accurate in the 1–5 rep range.
Example: 100 kg × 8 reps → Epley 1RM ≈ 127 kg; Brzycki ≈ 113 kg
Ref: Epley (1985); Brzycki (1993)
Tips
- 💡 Epley and Brzycki diverge as weight approaches 1RM. Test with a submaximal set, not a true max.
- 💡 Train at 70–85% of your 1RM for strength, 50–70% for hypertrophy.