Calculators
Barbell hip thrust one-rep max calculator
Enter the weight and reps of a recent set of the barbell hip thrust. With 135 lb for 8 reps, the Epley formula estimates a one-rep max of 171 lb.
One-rep max
Loads by percentage of your max
| % of max | Weight | Reps, estimated |
|---|---|---|
| 100% | 171 lb | 1 |
| 95% | 162 lb | 2 |
| 90% | 154 lb | 3 |
| 85% | 145 lb | 5 |
| 80% | 137 lb | 8 |
| 75% | 128 lb | 10 |
| 70% | 120 lb | 13 |
| 65% | 111 lb | 16 |
| 60% | 103 lb | 20 |
Which weight to use to build muscle
2 to 4 sets · 6 to 12 reps115 to 139 lb
To build muscle, the guide for this exercise uses 2 to 4 sets of 6 to 12 reps, ending each set with 1 to 3 reps in reserve. By the Epley formula, that is about 67% to 81% of your estimated max: with a max of 171 lb, about 115 to 139 lb per set.
The formula, step by step
Say your last good set was 135 lb for 8 reps.
Epley
max = weight × (1 + reps ÷ 30)
135 × (1 + 8 ÷ 30) = 135 × 1.27 = 171 lb
Brzycki
max = weight × 36 ÷ (37 − reps)
135 × 36 ÷ (37 − 8) = 4,860 ÷ 29 = 167.6 lb
What the studies say about hip thrust strength
In a 9-week trial, people who trained the hip thrust gained 26 kg (about 57 lb) more on their hip thrust 3-rep max than people who trained the squat. A 2026 meta-analysis of 20 trials found the same: hip thrust training raises hip thrust strength, and that strength did not carry over to the squat or to jumping.
Plotkin 2023
Plotkin DL, Rodas MA, et al. Hip thrust and back squat training elicit similar gluteus muscle hypertrophy and transfer similarly to the deadlift. Front Physiol. 2023;14:1279170.
Lin 2026
Lin S, et al. Acute and long-term effects of hip thrust training on athletic performance: a systematic review and meta-analysis. PeerJ. 2026.
Barbell hip thrust
For max strength, the guide for this exercise suggests 3 to 5 sets of 3 to 6 reps with 2 to 3 reps in reserve, once your form is solid.
How to do it
Barbell hip thrust
How it works
Both formulas turn a set done to fatigue into an estimate of the most you could lift once. They match at 10 reps; below 10, Epley comes out a little higher.
Use a recent set done with good form, and enter the reps you could have done: if you stopped after 8 with 2 more in the tank, enter 10. You do not need to test a true max.
Treat the result as an estimate. How many reps fit at a given percentage changes from person to person and from one exercise to another: in a meta-regression of 269 studies, people did more reps on the leg press than on the bench press at every load.
New to lifting? You do not need a one-rep max to start: the app finds your starting weights from the reps you have left in reserve.
One-rep max by exercise
Barbell back squat
One-rep max
Barbell Romanian deadlift
One-rep max
Barbell deadlift
One-rep max
45-degree leg press
One-rep max
Smith machine squat
One-rep max
Sources
Epley
Epley B. Poundage chart. In: Boyd Epley Workout. Lincoln (NE): Body Enterprises; 1985. p. 86.
Brzycki
Brzycki M. Strength testing: predicting a one-rep max from reps-to-fatigue. J Phys Educ Recreat Dance. 1993;64(1):88-90.
Reps, estimated
Nuzzo JL, Pinto MD, et al. Maximal Number of Repetitions at Percentages of the One Repetition Maximum: A Meta-Regression and Moderator Analysis of Sex, Age, Training Status, and Exercise. Sports Med. 2024;54(2):303-321.
Watch your max go up
Log your sets in the app and see your estimated max for each exercise, week after week.