Method Methodology Applications Evidence Calculator

Calculator

Enter HRV values manually or import them from an existing report.

Age*(years)

Age-specific reference percentiles cover 18–72 years.

Reference sex

HRV values

Optional:

Decimal points and decimal commas are both accepted. At least RMSSD or SDNN is required.

RMSSD(ms)

Primary five-minute HRV metric.

SDNN(ms)

Overall variability during the five-minute recording.

pNN50(%)

Frequency-domain data

LF and HF powerLF/HF ratio only

HF power(ms²)

Enter absolute spectral power in ms². Do not enter normalized units, percentages or log-transformed values.

LF power(ms²)

Enter absolute spectral power in ms². Do not enter normalized units, percentages or log-transformed values.

5HRV

A scientific calculator that analyses standardized five-minute HRV recordings using peer-reviewed research and age- and sex-specific reference populations.

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Method
Methodology
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Analysis
Applications
Evidence
Calculator
About

Scientific framework

Developed by Willem Gielen, Cardiologist and Internist, as a transparent approach to standardized five-minute HRV analysis in research and education.

5HRV provides contextual interpretation of HRV measurements for educational and professional reference. It does not diagnose disease, replace ECG review or substitute for clinical assessment.

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