The Lombardi One Rep Maximum calculator determines the maximum amount of force that can be generated in one maximal lift.
INSTRUCTIONS: Choose your preferred units and enter the following:
Max Weight: The calculator returns the one rep maximum weight in pounds. However, this can be automatically converted to other mass/weight units (e.g. kilograms) via the pull-down menu.
Wikipedia - https://en.wikipedia.org/wiki/One-repetition_maximum