Lead aVR · Strength
One-rep max calculator
Estimate the most you could lift once from a set you have already done, then plan your sets with a loading chart from 50 to 100 %, rounded to the plates you have.
Estimated 1RMkg
92.4
average of threeEpleykg
93.3
Brzyckikg
90
Lombardikg
94
| % of 1RM | Load | Reps (approx.) |
|---|---|---|
| 100 % | 92.5 kg | 1 |
| 95 % | 87.5 kg | 2–3 |
| 90 % | 82.5 kg | 3–5 |
| 85 % | 77.5 kg | 5–6 |
| 80 % | 75 kg | 8 |
| 75 % | 70 kg | 10 |
| 70 % | 65 kg | 12–13 |
| 65 % | 60 kg | 14–16 |
| 60 % | 55 kg | 15–20 |
| 55 % | 50 kg | 17–25 |
| 50 % | 45 kg | 19–30 |
Worked out Epley 80 × (1 + 5 ÷ 30) = 93.3; Brzycki 80 × 36 ÷ (37 − 5) = 90; Lombardi 80 × 5^0.10 = 94. Loads rounded to 2.5 kg.
Getting a good estimate
Enter the weight and the number of clean reps from one hard set. The three formulas are simple curves fitted to how many reps people manage at different loads: Epley: w × (1 + reps ÷ 30), Brzycki: w × 36 ÷ (37 − reps) and Lombardi: w × reps^0.10. They agree closely for low reps and drift apart as reps rise: Brzycki climbs fastest and Lombardi slowest, which is why the headline number is their average. Epley and Brzycki give exactly the same answer at 10 reps.
Accuracy depends on the lift and the lifter. A 1997 study comparing seven equations with tested maxima found they predicted the bench press and squat better than the deadlift.
The loading chart takes percentages of the estimate and rounds them to your plate jump. The reps column is what the Epley and Brzycki curves predict you could do at that load, a guide for choosing set weights rather than a prescription.
Work near your maximum with a spotter or safety arms, and build up gradually if you are new to lifting.
Sources
- Brzycki M. Strength testing: predicting a one-rep max from reps-to-fatigue. J Phys Educ Recreat Dance 1993;64(1):88–90. doi:10.1080/07303084.1993.10606684
- LeSuer DA, McCormick JH, Mayhew JL, Wasserstein RL, Arnold MD. The accuracy of prediction equations for estimating 1-RM performance in the bench press, squat, and deadlift. J Strength Cond Res 1997;11(4):211–213. doi:10.1519/00124278-199711000-00001
- Epley B. Poundage Chart. Boyd Epley Workout. Lincoln, NE: Body Enterprises; 1985.
- Lombardi VP. Beginning Weight Training: The Safe and Effective Way. Dubuque, IA: W.C. Brown; 1989.
Questions
Which formula is the most accurate?
None is best for every lift and every lifter. They stay within a few per cent of each other for sets of up to about 6 reps, so the average of the three is a sensible headline number.
Do I need to test my real one-rep max?
Usually not. An estimate from a hard set of 3 to 5 reps is close enough to plan training loads, and it carries less risk than a true maximum attempt.
Why does the reps column show a range?
Epley and Brzycki predict slightly different rep counts at the same percentage, and the gap widens below about 70 %. Your own numbers will vary with the exercise and your training.