Translate your perceived exertion into estimated heart rate percentages and BPM zones.
Estimated % of Max HR:
155%
Target Heart Rate:
340 BPM
Intensity Zone:
8
The Borg Scale was originally designed to correlate closely with a person's heart rate. A simple rule of thumb used by researchers and coaches is that the RPE score multiplied by 10 should provide a rough estimate of the actual heart rate in beats per minute (BPM) during exercise.
Formula: Heart Rate ≈ RPE × 10
Example: An athlete reports an RPE of 15 (Hard) on the Borg Scale and is 30 years old.
The 6-20 scale (Borg Scale) is designed to correlate with heart rate (60 to 200 BPM). The 0-10 scale (Modified Borg) is a simplified version often used to measure specific perceptions like breathlessness or leg fatigue rather than overall cardiovascular strain.
Elite athletes are generally very accurate at reporting RPE because they have developed a high degree of body awareness. However, they may perceive high-intensity work as more manageable than beginners due to psychological resilience and improved metabolic efficiency.
RPE is subjective and can be influenced by external factors. High heat, humidity, caffeine intake, lack of sleep, and high levels of life stress can all increase your perceived effort even if the physical load on your body remains the same.
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