Health & Fitness 2026-05-03 4 min read By Konvertibly Team

Blood Pressure Converter: Reading, Converting, and Understanding Your Numbers

Understand systolic and diastolic pressure, convert between mmHg and kPa, and know exactly what each blood pressure category means.

Blood Pressure: Reading Your Numbers and Converting Units

Blood pressure is measured as two numbers: systolic (peak pressure when the heart beats) over diastolic (pressure between beats), expressed as mmHg. In some clinical contexts and research, kilopascals (kPa) are used instead.

Unit Conversion

mmHg to kPa: value × 0.133322
kPa to mmHg: value × 7.50062

Example: 120/80 mmHg = 16.0/10.7 kPa

Blood Pressure Categories (AHA/ACC 2017)

Normal: <120 systolic AND <80 diastolic
Elevated: 120–129 systolic AND <80 diastolic
Stage 1 Hypertension: 130–139 OR 80–89 diastolic
Stage 2 Hypertension: ≥140 OR ≥90 diastolic
Hypertensive crisis: >180 systolic AND/OR >120 diastolic
Hypotension (low BP): <90/60

Factors That Affect Readings

Blood pressure varies throughout the day — highest in the morning, lower in the evening. Coffee, exercise, stress, and a full bladder can all elevate readings by 5–10 mmHg. Always rest for 5 minutes before measuring and take two readings 1–2 minutes apart.

White Coat Hypertension

Up to 20% of patients show elevated BP only in clinical settings. Home monitoring over several days gives a more accurate baseline.

Convert blood pressure units: Free Blood Pressure Converter