Plates & Pace

Strength one-rep max

Leg Press 1RM Calculator

Estimate your leg press max on the machine you use, then get training weights by percentage and your likely maxes for other rep counts.

Updated · Sources

Weight unit
StrengthLeg press 1RM

Estimated one-rep max

235.9 kg

90% of max
210 kg
Equation spread
225-242.5
Your set
180 × 10
WorkingAverage of 7 equations for 180 kg × 10 reps = 235.9 kg

Training weights

% of 1RMWeight
100%235 kg
95%225 kg
90%210 kg
85%200 kg
80%190 kg
75%175 kg
70%165 kg
65%155 kg
60%140 kg

Estimated rep maxes

RepsWeight
1 rep235 kg
2 reps225 kg
3 reps215 kg
4 reps210 kg
5 reps205 kg
6 reps200 kg
8 reps190 kg
10 reps180 kg
12 reps170 kg

How it works

Enter a recent set of leg presses taken close to failure. The calculator estimates your one-rep max on that machine and gives training weights and rep maxes.

Leg press numbers depend on the machine. The sled’s own weight, the angle and the range of motion all differ, so a max from one machine does not carry over to another. Use the estimate to plan training on the same machine.

The formula

Formula
w = weight lifted, r = reps completed

Epley      1RM = w × (1 + r ÷ 30)
Brzycki    1RM = w × 36 ÷ (37 − r)
Average    the mean of 7 published equations: Epley, Brzycki,
           Lander, Lombardi, Mayhew, O'Conner and Wathen

With 1 rep, the one-rep max is the weight lifted.

Worked example

You leg press 180 kg for 10 reps.

  1. Epley: 180 × (1 + 10 ÷ 30) = 240 kg.
  2. Brzycki: 180 × 36 ÷ (37 − 10) = 240 kg.
  3. The average of all seven equations is 235.9 kg.
  4. A working set at 80% is 188.7 kg, which rounds to 187.5 kg.

Rep counts on the leg press

Leg press sets are often done for 8 to 15 reps. The equations become less reliable above about 10 reps, so for the best estimate use a heavier set of 5 to 8 reps with a full, controlled range of motion.

Questions

Should I count the sled weight?

Count it the way you normally log your leg press, plates only or plates plus sled, and stay consistent. The estimate works either way, as long as your training weights use the same method.

Why is my leg press so much higher than my squat?

The machine supports your back, the sled runs on rails and the range of motion is usually shorter. The two numbers are not comparable.

How many reps give the best estimate?

Five to eight reps close to failure. Very high-rep sets spread the equations out.

Is it safe to test a true leg press max?

An estimate from a heavy set is enough for planning training and avoids the strain of a true max. If you do test, use the machine’s safety stops.

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Sources

  1. Brzycki M. Strength testing: predicting a one-rep max from reps-to-fatigue. Journal of Physical Education, Recreation and Dance. 1993;64(1):88-90.
  2. Mayhew JL, Ball TE, Arnold MD, Bowen JC. Relative muscular endurance performance as a predictor of bench press strength in college men and women. Journal of Applied Sport Science Research. 1992;6(4):200-206.
  3. LeSuer DA, McCormick JH, Mayhew JL, Wasserstein RL, Arnold MD. The accuracy of prediction equations for estimating 1-RM performance in the bench press, squat, and deadlift. Journal of Strength and Conditioning Research. 1997;11(4):211-213.
  4. Haff GG, Triplett NT, eds. Essentials of Strength Training and Conditioning. 4th ed. Human Kinetics; 2016. Percentage of 1RM and repetitions allowed.