5 reps → 1RM
52lb
average estimate
8 reps → 1RM
56lb
10 reps → 1RM
60lb
3 reps → 1RM
49lb
Show the math
Epley (5 reps) = 45 lb × (1 + 5 ÷ 30) = 52 lb
Brzycki (5 reps) = 45 lb × 36 ÷ (37 − 5) = 51 lb
If you lifted 45 lb for…
| Reps | Epley | Brzycki | Average 1RM |
|---|---|---|---|
| 1 rep | 45 | 45 | 45 |
| 2 reps | 48 | 46 | 47 |
| 3 reps | 50 | 48 | 49 |
| 4 reps | 51 | 49 | 50 |
| 5 reps | 52 | 51 | 52 |
| 6 reps | 54 | 52 | 53 |
| 7 reps | 56 | 54 | 55 |
| 8 reps | 57 | 56 | 56 |
| 9 reps | 58 | 58 | 58 |
| 10 reps | 60 | 60 | 60 |
| 11 reps | 62 | 62 | 62 |
| 12 reps | 63 | 65 | 64 |
If 45 lb is your one rep max
| % of 1RM | Load (lb) | About this many reps |
|---|---|---|
| 95% | 43 | 2 |
| 90% | 40 | 4 |
| 85% | 38 | 6 |
| 80% | 36 | 8 |
| 75% | 34 | 10 |
| 70% | 32 | 12 |
| 65% | 29 | 15 |
| 60% | 27 | 20 |
How to use it
- Enter your numbers. Switch between US and metric units at any time.
- Results update as you type, and the formula is shown so you can check it.
- Copy the link, save the plan on this device, or print it for your next appointment.
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These are estimates, not a diagnosis. A clinician can account for your health history and medicines.
Other weights
Common questions
What is my 1RM if I lift 45 lb for 5 reps?
About 52 lb, averaging the Epley and Brzycki formulas.
What is my 1RM if I lift 45 lb for 10 reps?
About 60 lb. Estimates get less precise above 10 reps.