1RM Lombardi
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
The Lombardi 1RM calculator estimates your 1-repetition maximum (1RM) based on the weight lifted and number of repetitions performed. It uses the formula 1RM = weight × (reps^0.1). This tool is useful for athletes and coaches who want to avoid direct 1RM testing, reducing injury risks. Ideal for strength training, it helps plan workouts with adjusted loads.
It works by applying a simplified equation that relates the used weight to the number of repetitions. For instance, if you lifted 80kg for 8 reps, the calculation would be 80 × (8^0.1) ≈ 90.5kg. This is a practical approximation but may not match an actual physical test result. Always consult a professional before using estimated values for intense training.
Do not use this calculator to replace direct physical tests in critical scenarios like competitions or high-intensity training. The formula assumes ideal technique and strength during repetitions. Factors like sleep, nutrition, or stress can affect real performance. Use it as a reference, not an absolute rule.
Frequently asked questions
How does the Lombardi 1RM formula work?
It estimates the maximum weight you can lift in one repetition by multiplying the used weight by (repetitions raised to the 1/10 power). For example, 80kg for 8 reps results in 80 × 8^0.1 ≈ 90.5kg.
Why use this calculator instead of direct testing?
Testing 1RM directly can cause injuries. This calculator provides a safe estimate, especially for regular training or when professional supervision is unavailable.
Are other factors besides weight and reps important?
Yes, the formula doesn't account for recovery, technique, or strength fluctuations. Use it as a supplement, but consult a trainer for personalized adjustments.
Can I fully trust the results?
The results are approximations. For higher accuracy, combine with supervised physical tests, especially before significantly increasing loads.
For which exercises is this calculator valid?
The formula is most accurate for compound movements like squats or bench press. Avoid using it for isolation exercises or complex techniques.