Blood Pressure Calculator
Calculate estimated mean arterial pressure and pulse pressure from systolic and diastolic readings.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
This calculator estimates MAP as (systolic + 2 × diastolic) ÷ 3 and pulse pressure as systolic − diastolic. These arithmetic estimates do not diagnose a condition; discuss blood-pressure readings with a qualified clinician.
Worked example
calculated with the default values below
Systolic 120 mmHg · Diastolic pressure 80 mmHg Mean arterial pressure 93.3 mmHg · Pulse pressure 40 mmHg · Systolic 120 mmHg
General background references
Disclaimer
These calculators are for general information only and are not a medical device, a diagnosis or a treatment plan. Reference ranges describe populations, not individuals, and do not account for pregnancy, medication, disability or athletic training. Discuss your own situation with a qualified healthcare professional.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
MAP = (S + 2D)/3; PP = S − D
- S
- Systolic pressure (mmHg)
- D
- Diastolic pressure (mmHg)
- MAP
- Mean arterial pressure (mmHg)
- PP
- Pulse pressure (mmHg)
Frequently asked questions
Why does mean arterial pressure weight diastolic twice as much?
For 120/80 mmHg, the MAP approximation is (120 + 2 × 80) ÷ 3 = 93.3 mmHg and pulse pressure is 40 mmHg. These are calculated values, not a diagnosis; a clinician should interpret blood-pressure readings.