Calculator
Rep Max Calculator
Quick answer
Enter a one-rep max. The page runs the inverse of the formula you pick and lists a load for one through twelve reps.
Epley is the default single formula. Average uses the mean of the inverses. These are estimates. A real 5RM can sit off the row, especially if the max itself was estimated.
Need a 1RM first? Use the one rep max calculator →
Estimates only. Testing a true max carries risk; use a spotter or safety arms. Not medical advice.
| Rep max | Load |
|---|---|
| 1RM | 200 lb |
| 2RM | 188 lb |
| 3RM | 182 lb |
| 4RM | 176 lb |
| 5RM | 171 lb |
| 6RM | 167 lb |
| 7RM | 162 lb |
| 8RM | 158 lb |
| 9RM | 154 lb |
| 10RM | 150 lb |
| 11RM | 146 lb |
| 12RM | 143 lb |
On this page
How does the rep max calculator work?
If M is the one-rep max, Epley's inverse is M / (1 + reps / 30). Brzycki's inverse is M × (37 − reps) / 36. The other inverses are on the homepage formula table and in the formula guide.
At one rep, every formula returns the max you typed. They separate as reps rise. That is the same disagreement you see when estimating upward.
What inputs does it need?
A max and a formula. If you do not have a tested max, estimate one on the one rep max calculator from a set you actually did, then paste it here.
The table stops at 12. Past that, the inverses are a poor description of a set you would want to take to failure.
Worked example with sample numbers
Example only: a 100 kg max under Epley. A 5RM is 100 / (1 + 5/30) = about 85.7 kg. A 10RM is 100 / (1 + 10/30) = 75 kg.
Brzycki on the same max puts the 10RM lower, because that curve is steeper on the way up and therefore lighter on the way down. Pick one formula and keep it if you are tracking weeks.
Common mistakes
Treating the 8RM row as a load you must hit for eight on the first week. It is a forecast. Leave a rep or two if the day is off.
Using a bench equation's rep row for a deadlift and being surprised. The rep max chart guide is the place to read the table before you load it.
FAQ
What is a rep max?
The heaviest load you can lift for that many reps. A 5RM is a five-rep max. The table estimates it from a 1RM.
Which formula should I invert?
The one you used to build the max. If the max is tested, Epley or the average is a reasonable default. Stay consistent.
Why does the table disagree with my set?
Because you are not the data set the equation was fit on, and because today's rep may not match the standard of the max.
Can I go the other way, from reps to a max?
Yes. That is the homepage calculator.
Does RPE change a rep max?
A true rep max is an all-out set, RPE 10. A set with reps left is not a rep max. Use the RPE calculator for those.