One Rep Max Calculator

Calculate your one rep max (1RM) using proven formulas to track strength progress and plan your training.

Calculate Your One Rep Max

Enter reps between 1-20 for best accuracy

Understanding One Rep Max

Your One Rep Max (1RM) is the maximum amount of weight you can lift for a single repetition of a given exercise. It's a key metric for strength training and helps determine appropriate training loads.

Why Calculate 1RM?

  • Training Programming: Determine appropriate weights for different rep ranges
  • Progress Tracking: Monitor strength gains over time
  • Goal Setting: Set realistic strength targets
  • Safety: Avoid attempting weights that are too heavy

Formula Accuracy

Different formulas work better for different rep ranges and individuals. The Epley formula is most commonly used and works well for most people in the 2-10 rep range. For best results, test with reps between 3-8.

Safety Note

These are estimates only. Always warm up properly and consider having a spotter when attempting heavy lifts. Start conservatively and build up gradually.