Squat 1RM notes
Squat estimates only mean something when depth is consistent. In IPF and USAPL-style powerlifting, the hip crease must pass below the top of the knee. A high squat may give a larger estimate, but it is not interchangeable with a competition-depth squat. Use the same depth standard each time you enter a rep set.
High-bar and low-bar squats can differ by 5-10% for the same lifter. Low-bar often allows more hip drive and a shorter moment arm at the knee, while high-bar usually demands more upright posture and quad strength. Shoes matter too: squat shoes can make depth easier and change the torso angle, while flat shoes may suit low-bar mechanics better.
A useful ratio check is squat to deadlift. Many trained lifters squat around 80-90% of their deadlift, though leverages and style can push that range around. If a calculator says your squat should suddenly match your deadlift after a high-rep set, retest with a heavier triple or five instead of trusting the inflated estimate.
Also separate beltless, belted, wrapped, and sleeved squat numbers. A belt can improve bracing immediately, and knee wraps can change the bottom position enough to make comparisons messy. For normal training blocks, use the variation you will actually program. If the next block is high-bar beltless work, a low-bar belted max may be too aggressive for useful percentage targets.
How the estimate works for this lift
e1RM still shows all six formulas because no single model owns the truth. Use the formula spread as a confidence range, keep the movement standard consistent, and round the result to loadable plates before building the percentage table.
For percentage programming, keep the same input style for at least one training block. Changing grip, stance, equipment, tempo, or range of motion can make the calculated max look like progress even when the actual adaptation is smaller. Consistency makes the calculator useful and keeps week-to-week comparisons honest over time.