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Ankle-Brachial Index Calculator

Calculate ABI as the ratio of ankle systolic pressure to brachial systolic pressure.

 

 

ABI

About this calculator

Use this calculator after you have already chosen the highest ankle and highest arm systolic pressures from the cuffs. ABI is ankle systolic ÷ brachial systolic. Typical adult sketches treat about 0.9–1.4 as the usual range; lower values raise concern for PAD, and very high values can reflect calcified vessels rather than healthy flow.

Pressures stay in mmHg. This is a ratio, not a diagnosis and not a full vascular study.

Ankle systolic: Highest ankle systolic pressure, in mmHg.

Brachial systolic: Highest arm systolic pressure, in mmHg.

ABI: Ankle-brachial index (dimensionless).