What it measures
The weight you could do a single barbell squat with, at the depth of your set. If your set reached parallel, the estimate holds for parallel, not for going lower.
Squat 1RM calculator
Calculate your barbell squat 1RM from a set you've already done, without loading your max on your back. Below you'll find your training weights from 50 to 100%.
It's an estimate for the technique of your set, not a test of your max.
Take it to your routine. In Mobbe you log your squat sets and see your estimated 1RM, for free.
Working weights and 1RM percentages
They update with the calculator. Right now they show a 1RM of 126 kg.
| % 1RM | Weight | To load | Reps |
|---|---|---|---|
| 50% | 63 kg138.9 lb | 62.5 kg | — |
| 55% | 69.3 kg152.8 lb | 70 kg | — |
| 60% | 75.6 kg166.7 lb | 75 kg | — |
| 65% | 81.9 kg180.6 lb | 82.5 kg | — |
| 70% | 88.2 kg194.4 lb | 87.5 kg | — |
| 75% | 94.5 kg208.3 lb | 95 kg | 10 |
| 80% | 100.8 kg222.2 lb | 100 kg | 8 |
| 85% | 107.1 kg236.1 lb | 107.5 kg | 5 |
| 90% | 113.4 kg250 lb | 112.5 kg | 3 |
| 95% | 119.7 kg263.9 lb | 120 kg | 2 |
| 100% | 126 kg277.8 lb | 125 kg | 1 |
| Reps | Epley | Brzycki |
|---|---|---|
| 1 | 100% | 100% |
| 2 | 93.8% | 97.2% |
| 3 | 90.9% | 94.4% |
| 4 | 88.2% | 91.7% |
| 5 | 85.7% | 88.9% |
| 6 | 83.3% | 86.1% |
| 7 | 81.1% | 83.3% |
| 8 | 78.9% | 80.6% |
| 9 | 76.9% | 77.8% |
| 10 | 75% | 75% |
| 11 | 73.2% | 72.2% |
| 12 | 71.4% | 69.4% |
“To load” rounds to 2.5 kg, what you can put together with plates. Reps come from Epley and are shown up to 12.
What your squat 1RM tells you
How accurate it is
In 67 untrained people, the estimate closely tracked the real one (correlation above 0.95). Even so, on the squat the mean difference was significant for 6 of the 7 formulas tested (LeSuer et al., 1997).
Which set to use
A recent, heavy set, with the same depth on every rep. If the last ones were higher, count only the ones that hit depth.
Before you test your squat max
If you want to confirm the number with a real rep, set this up first.
- Safety barsSet them a little below your lowest point. If you can't stand up, lower the bar onto them and step out from under it.
- No safety bars? Use spottersIf the rack has no safety bars, don't test it alone: you need one or two spotters who know how to hold the bar.
- The same depthGo down the same as in your set. A higher squat with more weight isn't your 1RM: it's a partial squat.
Warm up with increasing weights and rest a few minutes between the heaviest attempts. If you have pain or an injury, stick with the estimate and don't test your max.
How we calculate
The formulas, with the example set: 110 kg × 5 reps to failure. For pull-ups and dips, use the general 1RM calculator.
- Step 1
Epley
The formula the Mobbe app uses. With the example set: 110 × (1 + 5 ÷ 30) = 128.3 kg.
1RM = weight × (1 + reps ÷ 30)Epley, 1985. - Step 2
Brzycki and the average
110 × 36 ÷ (37 − 5) = 123.8 kg. Your estimated squat 1RM is the average of the two: 126 kg.
1RM = weight × 36 ÷ (37 − reps)Brzycki, 1993. - Step 3
RIR and RPE
If you didn't reach failure, we add the reps you had left (RIR). 110 kg × 5 at RPE 8 (2 in reserve) counts as 7 to failure: 133.8 kg.
reps to failure = reps done + RIRZourdos, 2016; Helms, 2016. - Step 4
How many reps to use
Reynolds et al. (2006) compared sets of 5, 10 and 20 reps to failure on the bench press and leg press: the set of 5 predicted 1RM best. They recommend not going above 10 reps with linear formulas like Epley. The calculator accepts up to 12.
Reynolds, 2006.
Sources
- Epley B. Poundage chart. Boyd Epley Workout. Lincoln, NE: Body Enterprises; 1985.
- Brzycki M. Strength testing: predicting a one-rep max from reps-to-fatigue. J Phys Educ Recreat Dance. 1993;64(1):88-90.
- Zourdos MC, Klemp A, Dolan C, et al. Novel resistance training-specific rating of perceived exertion scale measuring repetitions in reserve. J Strength Cond Res. 2016;30(1):267-275. doi:10.1519/JSC.0000000000001049
- Helms ER, Cronin J, Storey A, Zourdos MC. Application of the repetitions in reserve-based rating of perceived exertion scale for resistance training. Strength Cond J. 2016;38(4):42-49.
- Reynolds JM, Gordon TJ, Robergs RA. Prediction of one repetition maximum strength from multiple repetition maximum testing and anthropometry. J Strength Cond Res. 2006;20(3):584-592. doi:10.1519/R-15304.1
- 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. J Strength Cond Res. 1997;11(4):211-213.
Squat exercises
How to do each one step by step, with a photo and the muscles it works.
Guides to get more out of it
More calculators and routines
- Bench press 1RM calculatorYour bench max from one set, and how to test it without getting pinned under the bar.Calculate →
- Deadlift 1RM calculatorYour deadlift max and why the formulas can come up short on this lift.Calculate →
- Overhead press 1RM calculatorYour barbell overhead press max, standing and with no leg drive.Calculate →
Mobbe
Mobbe builds your plan with these numbers
Download Mobbe for free: it builds your routine with AI, log every squat set and see your estimated 1RM so you know what weight to use next.
