This tool helps medical professionals and students convert between the Heart Rate (BPM) and the R-R interval (ms) typically measured on an electrocardiogram (ECG).
Calculated Heart Rate:
75 BPM
Calculated R-R Interval:
800 ms
The R-R interval represents the time between two consecutive R waves on an ECG. Heart rate is derived from this time gap.
Formula: HR (BPM) = 60,000 / R-R interval (ms)
HR (BPM) = 60,000 / R-R interval (ms)
If an ECG strip shows a consistent R-R interval of 750ms, the calculation follows a simple ratio.
A normal R-R interval typically ranges between 600ms and 1000ms, corresponding to 60-100 BPM.
There are 60 seconds in a minute, and each second has 1,000 milliseconds, totaling 60,000ms per minute.
As heart rate increases (tachycardia), the time between heartbeats decreases, resulting in a shorter R-R interval.
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