One Rep Max Calculator – Estimate Your Max Lifting Power
The One Rep Max Calculator helps you estimate the maximum amount of weight you can lift for a single repetition of a given exercise—your 1RM (One Rep Max). Whether you're strength training, bodybuilding, or testing your limits, this tool is essential for setting safe and effective workout goals.
At Calculators.at, our free 1RM Calculator gives you fast, reliable results to guide your strength training program.
🔍 What Is One Rep Max (1RM)?
One Rep Max (1RM) is the maximum weight you can lift in a single repetition of an exercise (e.g., squat, bench press, deadlift). Knowing your 1RM helps you:
- 💪 Gauge your strength level
- 📈 Create personalized workout plans
- 🔢 Set percentages for progressive overload
- ⚖️ Avoid lifting too much or too little weight
🧮 How the One Rep Max Calculator Works
To use the 1RM calculator, simply enter:
- 🏋️ Weight lifted
- 🔁 Number of reps performed (≤10)
The calculator uses formulas such as Epley, Brzycki, or Lombardi to estimate your 1RM.
Example:
- Weight: 100 kg
- Reps: 5
- Estimated 1RM ≈ 116.7 kg (Epley formula)
✅ Why Use a 1RM Calculator?
- 📊 Set realistic goals based on current strength
- 🧠 Train smarter with science-backed percentages
- 🏆 Measure progress over time
- ⚖️ Reduce injury risk by avoiding overtraining
- 📋 Design structured hypertrophy, strength, or power routines
🎯 Common Use Cases
- 🧱 Strength training: Use 75–90% of 1RM for low-rep heavy lifts
- 🔥 Hypertrophy: Use 65–75% of 1RM for muscle growth
- 🏃♂️ Endurance training: Use 50–60% of 1RM for high-rep workouts
👥 Who Should Use It?
- 🏋️♂️ Lifters and strength athletes
- 🧑🎓 Fitness coaches and personal trainers
- 🧍 Beginners tracking strength gains
- 📈 Anyone building a progressive workout plan
- 🧪 Sports scientists and gym enthusiasts