Standard Drink Calculator

How many drinks of the size and strength below.
Typical beer 4-6%, wine 12-14%, spirits 40%.
Metric uses kilograms and centimetres; US uses pounds with feet and inches; UK uses stones and pounds.
US standard drinks (14 g each)
3.0000
Blood Alcohol (BAC) Calculator
Pure alcohol consumed
42.0003 g
Pure alcohol consumed
53.232 mL
UK alcohol units (10 mL each)
5.3232
Over the legal limit
not calculated
Typical effects at this BAC
Switch to the blood alcohol mode to estimate BAC.
Worked out from NHTSA, Office of Program Development and Evaluation - Computing a BAC Estimate (the Widmark form BAC = A x 5.14 / (W x r) - 0.015 H, with r = 0.68 men and 0.55 women) and 4 other sources.
UK guidance is to keep to 14 units a week, spread over three or more days, with several drink-free days.
This is a population-average estimate, not a measurement. Real BAC varies widely with absorption, food, sex, medication, liver function and tolerance, and can still be rising after the last drink. Never use it to decide whether it is safe or legal to drive. The only safe amount of alcohol before driving is none.

How this is worked out

5 steps
  1. Total liquid = 3 x 12 fl-oz = 1064.65 mL
  2. Pure ethanol = 1064.65 mL x 5% = 53.232 mL
  3. Mass of ethanol = 53.232 mL x 0.789 g/mL = 42 g
  4. US standard drinks = 42 g / 14 g = 3
  5. UK units = 53.232 mL / 10 mL = 5.323

Results are general information, not financial, tax, legal, medical or engineering advice.