Set & Rep Calculator Formula

Understand the math behind the set & rep calculator. Each variable explained with a worked example.

Use the Set & Rep Calculator

Formulas Used

Working Weight

weight = working_weight

Target Reps

reps = target_reps

Total Volume

volume = round(working_weight * target_reps * num_sets)

Intensity

intensity_display = goal

Variables

VariableDescriptionDefault
one_rmEstimated 1RM(lbs)225
goalTraining Goal75
num_setsNumber of Sets4
working_weightDerived value= round(one_rm * goal / 100 / 5) * 5calculated
target_repsDerived value= (goal > 80) * 4 + (goal > 65) * (goal <= 80) * 10 + (goal <= 65) * 17calculated

How It Works

How to Choose Sets and Reps

Training Goal Guidelines

  • Strength: 3-5 reps at 85%+ 1RM, 3-6 sets
  • Hypertrophy: 8-12 reps at 65-80% 1RM, 3-5 sets
  • Endurance: 15-20+ reps at 50-65% 1RM, 2-4 sets

    • Working Weight

    The calculator rounds to the nearest 5 lbs for practical plate loading.

    Volume = Sets x Reps x Weight

    Total volume is the key metric for progressive overload and training tracking.

    Worked Example

    Hypertrophy training with a 225 lb 1RM, 4 sets.

    one_rm = 225goal = 75num_sets = 4
    1. 01Working weight = 225 * 0.75 = 168.75, rounded to 170 lbs
    2. 02Target reps for hypertrophy = 10
    3. 03Volume = 170 * 10 * 4 = 6,800 lbs

    Frequently Asked Questions

    How many sets should I do per exercise?

    3-4 sets is effective for most goals. Beginners may start with 2-3 sets. Advanced lifters may benefit from 4-6 sets.

    Should I train to failure?

    Training 1-2 reps short of failure (RIR 1-2) is generally recommended. Going to failure occasionally is fine but doing so every set increases fatigue without proportional gains.

    Can I mix rep ranges?

    Yes. Many effective programs use different rep ranges on different days or for different exercises to develop multiple qualities simultaneously.

    Ready to run the numbers?

    Open Set & Rep Calculator