1RM Calculator — Epley, Brzycki, Lombardi
Inputs & Actions
Results
Epley
Brzycki
Lombardi
Working 1RM avg
Tip: Best accuracy usually comes from well-executed sets in the 2–10 rep range.
%1RM Load Table
Loads below are based on Working 1RM. Click “Use average” or any result to set it. Update reps/weight and recalc anytime.
| % of 1RM | Typical Reps | Load (kg) |
|---|---|---|
| These are guidelines; actual reps vary by lift, tempo, rest, and training status. | ||
How the 1RM formulas work
Epley
1RM = Weight × (1 + Reps/30)
Brzycki
1RM = Weight ÷ (1.0278 − 0.0278 × Reps)
Lombardi
1RM = Weight × Reps^0.10
Note: Treat estimates as starting points. Use a spotter and proper technique for heavy attempts.
How the 1RM formulas work
Note: Best accuracy is usually from well-executed sets in the 2–10 rep range.
1RM Calculator – FAQ
Which 1RM formula should I use?
Epley and Brzycki are widely used and typically close in the 2–10 rep range. Lombardi uses a power curve and may differ more at higher reps.
How accurate are 1RM estimates?
They’re estimates. Results vary with rep range, lift selection, technique, fatigue, and training status. Treat them as starting points.
Can I enter weight in kg or lb?
Yes. The math is unit-agnostic—just be consistent for weight and results.
Is my data private?
Yes. All calculations run in your browser. No inputs are stored or uploaded.