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Universal International Converter

Universal BAC Unit Converter.

Instant two-way conversion between percentage (US/AU), Promille ‰ (EU/Germany), mg/100ml (UK/Ireland), and breath alcohol concentrations.

US / AU / CA
%
g of alcohol per 100ml blood
EU / DE / PL / SE
g of alcohol per 1kg / 1L blood
UK / IE / IN
mg
mg of alcohol per 100ml blood
Breathalyzer BrAC
µg
Micrograms per 100ml breath
Common Legal Presets:

International Alcohol Measurement Standards

Unit FormatRegion / Standard0.05% BAC Equiv0.08% BAC EquivMathematical Basis
% BACUS, Australia, Canada0.050%0.080%g ethanol / 100 ml blood
Promille ()Germany, Scandinavia, EU0.500 0.800 g ethanol / 1000 g blood
mg/100mlUK, Ireland, India50.0 mg80.0 mgmg ethanol / 100 ml blood
µg/100ml BrACUK / EU Breathalyzers22.0 µg35.0 µg2,300:1 Blood-to-Breath Partition

The Blood-to-Breath Partition Ratio

Breathalyzers measure the concentration of alcohol in deep alveolar breath. Most statutory legal systems assume a fixed partition ratio between 2,100:1 (US) and 2,300:1 (UK/Europe), meaning 2,300 ml of expired lung air contains the same quantity of alcohol as 1 ml of blood.

Promille (‰) vs Percent (%)

In continental Europe, blood alcohol is universally reported in promille (‰) (parts per thousand). Converting between percentage and promille is a direct factor of 10: 0.05% BAC = 0.50‰ Promille.