Baseline

Back squat one rep max calculator

Enter a weight and the repetitions you managed on the back squat. The five equations below were fitted to different data and give different answers; the spread between them tells you how much to trust the estimate.

Enter your set

Units
kg
reps

Result

These are estimates from population-level equations, not a measurement of you and not medical advice. Individual results vary widely. Talk to a doctor or a registered dietitian before making significant changes to how you eat or train.

The back squat specifically

The back squat is the other lift the 1RM equations were largely built on, and estimates transfer well to it.

The five equations were validated mostly on bench press and squat data. reliable, for the same reason as the bench press: it is well represented in the original validation data.

  • Depth changes the answer. A set to parallel and a set well below it are different lifts, and comparing estimates across them is meaningless.
  • High-bar and low-bar positions differ by several per cent for most lifters.
  • Squats tend to allow more repetitions at a given percentage than upper-body lifts, so estimates from high-rep sets read high.
Typical reps
3 to 8
Category
Lower body

Estimated back squat max by weight and reps

Epley estimates in kilograms. Read across from the weight you lifted and down from the repetitions you managed. Columns beyond ten repetitions are shown but are the least reliable.

Estimated one rep max by weight lifted and repetitions
Weight1 reps2 reps3 reps5 reps8 reps10 reps12 reps
40 kg41.342.74446.750.753.356
60 kg62646670768084
80 kg82.785.38893.3101.3106.7112
100 kg103.3106.7110116.7126.7133.3140
120 kg124128132140152160168
140 kg144.7149.3154163.3177.3186.7196
160 kg165.3170.7176186.7202.7213.3224

Percentage table

Training loads as a share of a 100 kg maximum, with the repetitions each percentage typically allows. Scale proportionally to your own estimate.

Percentage of one rep max with expected repetitions
PercentageLoad from 100 kgApproximate reps
50%50 kg30
55%55 kg25
60%60 kg20
65%65 kg16
70%70 kg13
75%75 kg10
80%80 kg8
85%85 kg5
90%90 kg3
95%95 kg2

Rep-max conversion

What a 100 kg estimated maximum corresponds to at each repetition count, and how the five equations compare for a 100 kg set of five.

Rep max conversion and formula comparison
RepetitionsLoad for a 100 kg max
196.8 kg
293.8 kg
390.9 kg
585.7 kg
878.9 kg
1075 kg
1271.4 kg
The five equations compared for 100 kg times five
Formula100 kg × 5 reps
epley116.7 kg
brzycki112.5 kg
lombardi117.5 kg
oconner112.5 kg
wathan116.6 kg

Questions

How do I estimate my back squat max?
Take a set to or near failure, enter the weight and the repetitions, and the equations do the rest. A heavy triple gives a far more reliable estimate than a set of twelve, because all five equations were validated in the two to ten repetition range.
Are 1RM estimates accurate for the back squat?
Reliable, for the same reason as the bench press: it is well represented in the original validation data.
Which formula should I use?
Wathan and Epley track measured data across the widest range; Brzycki is the most conservative and is exact at a single repetition. The average of all five is a more defensible single number than any one of them, and the spread between them tells you how much confidence the estimate deserves.
What repetition range suits the back squat?
This lift is usually trained in the 3 to 8 repetition range. Estimates taken from within that range are the most trustworthy, because they sit closest to where the equations were fitted.
Should I test a true maximum instead?
Only if you need the number for competition, and then with a spotter and a full warm-up. For programming, an estimate from a heavy triple is nearly as useful and costs far less recovery and risk.