GBC
Density, Strength & Purity

Proof

Modern equivalent

57.1% ABV (at 100° UK Proof)

Traditional spirit strength verified by whether gunpowder soaked in alcohol would ignite.

Historically, excise men tested high-proof spirits by pouring them over gunpowder and applying a flame; if it burned steadily without dampening, it passed "proof."

Convert it

Whisky Measures

Part of a system

Sikes's Hydrometer Scale

Related units

Dram

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