1-Rep Max Calculator — ReppySetGo

It's hard to find your true 1-rep max on heavy compounds without a spotter, so if you train alone as I do this tool is for you. It will give you an estimated 1-rep max based on your best multi-rep working set. It includes the four major 1-rep max formulas: Epley, Brzycki, Lombardi, and Mayhew.

Epley is the most widely used and works well across a broad rep range. Brzycki tends to be more conservative, particularly at higher rep counts. Lombardi can overestimate for lifters who favour higher reps. Mayhew was derived from bench press data specifically, so it's most at home there.

The percentage table shows splits at 10% intervals from 90% down to 10% of your estimated 1RM. If your programme calls for working at 80% of your max, you can use this to find the right weight to put on the bar. You can choose from seven popular compound exercises, or set it to general for any lift not on the list.

If you add your bodyweight and select one of the listed compounds, the tool will give you a rough strength level benchmark — from novice through to elite — based on your bodyweight-to-1RM ratio. If you set a "general exercise", you have the option to name it which is necessary if you wish to add it to your report.

You can add as many exercises as you want to your report, though you can only have one instance of each. At the bottom of the main page of the site is a DOWNLOAD button where you can download a PDF with all the figures you've just collected.