Heart Rate Interval Converter
Convert between Milliseconds (RR Interval) and Beats Per Minute
MS to BPM
BPM to MS
Calculated Rate:
0BPM
Frequency:
0Hz
Based on standard 60,000ms per minute calculation.
Understanding the MS to BPM Conversion
The relationship between milliseconds (ms) and beats per minute (BPM) is reciprocal. This conversion is critical in two main fields: cardiology and audio engineering. In a medical context, the time between heartbeats (often measured as the RR interval on an ECG) determines the heart rate. In music, this calculation determines delay times and oscillator frequencies based on tempo.
The Formulas
Because there are 60 seconds in a minute, and 1,000 milliseconds in a second, there are exactly 60,000 milliseconds in one minute.
- To find BPM from MS: Divide 60,000 by the duration in milliseconds.
BPM = 60,000 / ms - To find MS from BPM: Divide 60,000 by the heart rate in BPM.
ms = 60,000 / BPM
Medical Context: The RR Interval
In cardiac electrophysiology, the "RR interval" is the time elapsed between two successive R-waves of the QRS signal on the electrocardiogram (ECG). This duration is measured in milliseconds.
- Normal Resting Heart Rate: 60 to 100 BPM (equivalent to 1000ms to 600ms).
- Bradycardia: Below 60 BPM (intervals longer than 1000ms).
- Tachycardia: Above 100 BPM (intervals shorter than 600ms).
Common Conversions Reference Table
| Heart Rate (BPM) | Interval (ms) | Frequency (Hz) | Condition (Resting) |
|---|---|---|---|
| 40 BPM | 1500 ms | 0.67 Hz | Bradycardia |
| 60 BPM | 1000 ms | 1.00 Hz | Normal (Low) |
| 80 BPM | 750 ms | 1.33 Hz | Normal (Avg) |
| 100 BPM | 600 ms | 1.67 Hz | Normal (High) |
| 120 BPM | 500 ms | 2.00 Hz | Tachycardia |
| 180 BPM | 333.3 ms | 3.00 Hz | Extreme Exertion |
Why Calculate Frequency (Hz)?
Frequency in Hertz represents the number of cycles per second. Since BPM is cycles per minute, you can calculate Hertz by dividing the BPM by 60. For example, a heart rate of 60 BPM beats exactly once per second, resulting in a frequency of 1 Hz.