One Rep Max (1RM) Calculator: Epley, Brzycki and Lombardi
Enter the weight you lifted and how many reps you managed to estimate your one-rep max, without testing a maximal lift.
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Estimated one-rep max
74.8kg
- Epley
- 76 kg
- Brzycki
- 74.5 kg
- Lombardi
- 73.9 kg
An estimate for general information. Lift within your ability and stop if anything hurts.
Warm up well and use a spotter for heavy sets.
Training loads (% of 1RM)
| % of 1RM | Load | About this many reps |
|---|---|---|
| 100% | 74.78 | 1 |
| 95% | 71.04 | 2 |
| 93% | 69.55 | 3 |
| 90% | 67.31 | 4 |
| 87% | 65.06 | 5 |
| 85% | 63.57 | 6 |
| 83% | 62.07 | 7 |
| 80% | 59.83 | 8 |
| 77% | 57.58 | 9 |
| 75% | 56.09 | 10 |
| 70% | 52.35 | 11 |
| 67% | 50.11 | 12 |
| 65% | 48.61 | 15 |
How to use
- Choose kg or lb and enter the weight lifted.
- Enter the reps you completed with good form (best between 2 and 10).
- Read your estimated 1RM and the training loads table.
Good to know
Epley: 1RM = weight × (1 + reps ÷ 30). Brzycki: weight × 36 ÷ (37 − reps). Lombardi: weight × reps^0.10. For 100 kg × 5 reps they give 116.7, 112.5 and 117.5 kg; the average is about 115.5 kg.
The % table uses the NSCA load–repetition chart: about 95% of 1RM for 2 reps, 87% for 5, 75% for 10 and 67% for 12. Use it to pick working weights, for example 75–80% for sets of 8–10.
Estimates are best from sets of 2–10 reps taken close to failure; above about 10 reps they get less reliable. Testing a real 1RM needs a warm-up, a spotter and good technique; beginners and people with joint or heart problems should not attempt maximal lifts.
Questions
Which 1RM formula is most accurate?
They are close below 10 reps. Brzycki tends to read lower and Lombardi higher; the average is a sensible middle value.
How many reps should I use?
A set of 3–6 reps done to near failure gives the most reliable estimate.
Is it safe to test my one-rep max?
Only with proper warm-up, a spotter or safety bars, and good technique. Estimating it from a heavier set of a few reps is safer.
What weight should I use for 10 reps?
About 75% of your 1RM according to the NSCA chart.
Does this work for all exercises?
It works best for big lifts such as squat, bench press and deadlift. Small isolation exercises can differ.