Leg Press to Squat Calculator

There is no exact conversion from leg press to squat. Machines differ, the sled has its own weight, and a squat needs balance and trunk strength that a leg press does not. This calculator uses the one published equation we found that was built from men who did both lifts¹, adjusted for your type of machine.

What the Leg Press to Squat Estimate Measures

It estimates your one rep max (1RM) in a barbell back squat to parallel, with your thighs about level with the floor. It is not a measurement. It shows what men with a leg press like yours tended to squat in one study, so your real number could be well above or below it.

The Formula

Leg press 1RM = (weight loaded + sled weight) x (1 + reps / 30), or the load itself for a single rep

45 degree equivalent = leg press 1RM on a 45 degree sled, or leg press 1RM x 1.414 on a vertical or seated machine

Estimated squat 1RM = 0.354 x 45 degree equivalent + 2.98 kg (6.57 lb)

Likely range = estimated squat 1RM x 0.75 to estimated squat 1RM x 1.25

The squat line comes from a study of 60 men who did a 10-rep max on a 45 degree leg press and a free weight parallel squat¹. Their whole-group equation was squat = 0.354 x leg press + 2.235 kg, using 10-rep loads¹. Converting both lifts to 1RMs with Epley's equation, as our One Rep Max Calculator does, scales 2.235 kg up to 2.98 kg.

The 1.414 is 1 divided by sin 45 degrees. Gravity pulls a 45 degree sled along its rails with only about 71 percent of the load², while a vertical press or a weight stack resists with about all of it. So 100 kg on those machines is like roughly 141 kg on a 45 degree sled.

How This Calculator Computes Your Result

Pick lb or kg, then enter the weight you loaded, your reps (1 to 15) and your machine type. On a plate loaded sled, add the empty sled's weight if you know it, since it is real load. A single rep counts as your leg press 1RM.

The tool shows your estimated squat 1RM and likely range, rounded to the nearest 5 lb or 2.5 kg, and your leg press 1RM on that machine. Adding your body weight shows the estimate as a multiple of it but does not change it, because body mass did not improve the prediction in the study¹.

What Your Result Means

The middle number is what a typical man in the study would squat with your leg press. The range is plus or minus 25 percent, and it is wide on purpose: leg press results explained only about 25 percent of the differences in squat strength among novices and 55 percent among advanced lifters¹.

Estimates for a 45 degree sled, sled weight not entered, sets of 10 reps:

On these numbers, a 45 degree leg press 1RM is about 2.6 to 2.8 times the squat 1RM. Squat practice, technique and depth often decide where you land in the range.

Why Leg Press and Squat Numbers Differ

• Angle. A 45 degree sled carries about 71 percent of its load along the rails, plus a little rail friction on the way up². A vertical press carries all of it.

• The sled. The empty sled is real weight that most people do not count, and it differs between machines.

• Machine labels. In one lab study of ten lower body machine exercises, the load shown on the machines rarely matched the true load, so the researchers weighed it³.

• Your body. In a squat you lift your body as well as the bar while balancing and keeping your trunk upright. On the leg press the seat holds your back, and depth and foot position vary.

• Reps. A review of 269 studies found people do more reps on the leg press than on the bench press at the same percent of their max⁴. So a 1RM from a long leg press set may run high, and sets of about 10 reps or fewer work best.

• Training. In a 10-week study of 26 untrained men, squat training raised squat 1RM more than three times as much as leg press training, while leg press gains were similar in all groups⁵.

How to Test Your Squat Safely

Treat the estimate as a starting guide, not a weight to load on day one. If you are new to squats, learn the movement with light loads first. When you are ready, these are the NSCA testing steps as summarised by Human Performance Resources by CHAMP⁶:

1. Warm up with a light load you can lift 5 to 10 times, then rest 1 minute.

2. Add 30 to 40 lb (10 to 20 percent) and do 3 to 5 reps, then rest 2 minutes.

3. Move to a near max load you can lift 2 to 3 times, then rest 2 to 4 minutes.

4. Add weight and try 1 rep. After a miss, rest 2 to 4 minutes and drop 15 to 20 lb (5 to 10 percent).

5. Stop at the heaviest single you can lift with good technique.

Squat inside a rack with the safety bars set just below your lowest point, or use a spotter. If you train alone without a spotter, a multiple-rep test is a good option, but keep back squat tests to 5 reps or fewer because form breaks down in longer sets⁶. Our Squat Max Calculator turns that set into a 1RM.