This calculator uses the Epley formula to estimate your one-rep max (1RM). From there, we can predict your rep maxes, calculating how much weight you can lift for 1–30 reps.
Rep Max Wizard
Calculator Tool
Estimated 1RM: pounds
Repetitions
Weight
Percentage of 1RM
These estimations aren't perfectly accurate, but they should get you into the right ballpark.
We all have different genetics and training histories. Some of us are better at lifting heavier. Others are better at lifting lighter. Still, this should give you a rough idea of how much weight to load on the bar.
Shane Duquette is the co-founder of Outlift, Bony to Beastly, and Bony to Bombshell. He's a certified conditioning coach with a degree in design from York University in Toronto, Canada. He's personally gained 70 pounds and has over a decade of experience helping over 10,000 skinny people bulk up.
Marco Walker-Ng is the co-founder and strength coach of Outlift, Bony to Beastly, and Bony to Bombshell, and is a certified trainer (PTS) with a Bachelor's degree in Health Sciences (BHSc) from the University of Ottawa. His specialty is helping people build muscle to improve their strength and general health, with clients including college, professional, and Olympic athletes.
