Strength Training
Epley one rep max estimate
The simpler of the two forms. The load is multiplied by a factor that grows linearly with the number of repetitions completed.
The Formula
1RM = w x (1 + reps/30)
The simpler of the two forms. The load is multiplied by a factor that grows linearly with the number of repetitions completed.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| w | Weight lifted | kg or lb | The load you actually completed for the given reps, not a weight you merely attempted. |
| reps | Repetitions completed | reps | Best kept at ten or fewer; the estimate loses meaning as this grows. |
| 1RM | Estimated one rep max | kg or lb | A prediction of maximal strength, not a measured maximum. |
What Each Symbol Means
wkg or lb
Weight lifted
The load you actually completed for the given reps, not a weight you merely attempted.
repsreps
Repetitions completed
Best kept at ten or fewer; the estimate loses meaning as this grows.
1RMkg or lb
Estimated one rep max
A prediction of maximal strength, not a measured maximum.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate one rep max page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate One Rep Max, filed under Health. Every number the guide produces comes from substituting into this one line.