e1RM calculator
Type one set you finished, in lb or kg, and see the estimated one-rep max (e1RM) it shows, without having to test a single.
Type the weight and the whole reps of one set you finished.
How the estimate is worked out
The estimate is the Epley formula: the weight × (1 + reps ÷ 30). Five reps at 100 kg reads as about 117 kg. It is the same number Rebar records for your lifts.
Reps past 10 are counted as 10. Long sets say more about endurance than about a single heavy rep, and left uncapped they would inflate the estimate. The set still counts; it just can't claim more than a set of 10 would.
A set past the limits of a real set (heavier than any lift on record, or hundreds of reps) gets no estimate at all. That usually means a typo or the wrong units. Pounds show as whole numbers and kilograms to a tenth: an estimate has no finer precision than that.