Free Tools
1-Rep Max (1RM) Calculator
In short
Your one-rep max (1RM) is the most you could lift once. This tool estimates it from a set you actually did, then gives you the working weights for strength, muscle and endurance so you can train at the right load.
You never need to test a true max to train smart. Do a solid set to near-failure, enter the weight and reps, and this gives your estimated 1RM plus practical training loads.
How it works
- We use the Epley formula: 1RM = weight × (1 + reps ÷ 30).
- Strength work sits around 85–95% of 1RM.
- Muscle building sits around 67–80%; endurance below 67%.
Frequently Asked Questions
How accurate is it?+
Very good up to about 5 reps; less accurate at high reps. Use a set of 3–8 reps for the best estimate.
Should I test my real 1RM?+
Rarely necessary and riskier solo. Estimating from a submaximal set is safer and accurate enough for programming.
Ready to start?
Train at our Putra Heights centre, your home, or your condo gym