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Health · Cardiovascular & Blood Pressure

Ankle–Brachial Index Calculator

Calculate left and right ABI from professionally measured ankle and brachial pressures.

Health · Cardiovascular & Blood Pressure

Enter your measurements

Professional entered-value arithmetic · private in-browser calculation
Professional intended use

This route reproduces arithmetic from verified source measurements. It does not validate the measurements, diagnose, select treatment, or replace the applicable clinical protocol.

Health values stay in this browser tab. They are not added to the URL, analytics, storage, or a cloud record.

Health result

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Enter valid values to see the result.

Your entries are calculated in this browser and are not submitted to 365CALCS.COM.

Quick guide

How to use this calculator

  1. Use the labels and unit notes to enter the requested measurement, date, time, or observation exactly as recorded.
  2. Check the visible method, population, and unit basis before using the result; switch modes rather than converting values mentally.
  3. Read the calculation audit and limitations together. The result supports measurement or tracking and does not replace diagnosis, treatment, or urgent medical assessment.

Calculation method

How the ankle–brachial index calculator works

ABI for each leg = higher ankle-artery pressure ÷ higher entered brachial pressure.

The result describes only the entered observations. It does not classify cardiovascular health, diagnose a condition, predict an event, or recommend treatment.

Worked example

Ankle–Brachial Index example

Arms 130 and 126 mm Hg; left ankle 120/118 and right 110/108 gives ABI 0.923 left and 0.846 right.

ABI for each leg = higher ankle-artery pressure ÷ higher entered brachial pressure.

Supported inputs

Precision and limits

Supported purpose

Validated Doppler technique, rest, cuff selection, arterial compressibility, waveform review, and protocol-specific interpretation are required; this calculator does not diagnose PAD.

Measurement quality

The output is only as reliable as the entered measurement, device, timing, units, and applicable reference population. Recheck unexpected values against the original record.

Clinical boundary

This calculator does not diagnose a condition, choose treatment, change medication, or determine that an urgent symptom is safe to monitor at home. Contact an appropriate health professional or local emergency service when the situation may be urgent.

Privacy

Entered health values and results stay in this browser tab. They are not placed in URLs, analytics, logs, local storage, session replay, or a cloud record by this calculator.

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