One-rep max from a set

What your number means

The middle value is the best guess at the most you could lift once today, and the range shows how far the formulas disagree. From a set of 6 or fewer the range is tight, and past 10 reps it's a rough figure. Your ratio to bodyweight lets you compare yourself with yourself over time, and the squat with Gyroscope's training bands.

Use it to set your working weights. About 75% of the middle is a weight most people can lift about 10 times, and about 86% about 5 times (Epley's formula). Load it on the plate calculator, and estimate again from a new set every four to eight weeks. A middle value that keeps rising means the program is working. What are good strength standards for my age and weight?

The seven formulas

With w the weight and r the reps: Epley w(1 + r/30), Brzycki w × 36/(37 − r), Lander 100w/(101.3 − 2.67123r), Lombardi w × r^0.10, Mayhew 100w/(52.2 + 41.9e^−0.055r), O'Conner w(1 + 0.025r) and Wathen 100w/(48.8 + 53.8e^−0.075r). At one rep, every formula gives back the weight you lifted.

For 185 lb for 5 reps, they range from 208 to 220 lb, with the middle at 216. At 10 reps the same weight gives 231 to 249, and past 10 the formulas spread apart. In a study of 67 untrained students, every formula tracked the real max closely, and every one underestimated the deadlift (LeSuer 1997).

Why a range

People vary. Across 269 studies and 7,289 people, the average was about 5 reps at 90% of a max and about 15 at 70%, with a wide spread between people, and more reps on the leg press than the bench (Nuzzo 2024). A one-number calculator hides that.

There are no bench press levels here: the only big tables are self-reported lifts on a commercial site. The squat gets Gyroscope's training bands, and every lift gets its ratio to your bodyweight. Score it beside your other tests in How strong am I?