How many units are in a glass of port?
1units
That is a 50ml measure at 20% ABV. One UK unit is 10ml of pure alcohol. The weekly guideline of 14 units works out at about 14 of these across a whole week.
Port, sherry and other fortified wines are around 15% to 22% ABV and are served in small measures, usually 50ml or 75ml. The small glass hides a strong drink.
Units by size and strength
| Drink | Size | Strength | Units |
|---|---|---|---|
| Measure (50ml) of 20% portMost common | 50ml | 20% | 1 |
| Measure (75ml) of 20% port | 75ml | 20% | 1.5 |
| Measure (50ml) of 15% sherry | 50ml | 15% | 0.8 |
| Wine glass (125ml) of 20% port | 125ml | 20% | 2.5 |
| Bottle (750ml) of 20% port | 750ml | 20% | 15 |
How this is worked out
units = volume (ml) × ABV (%) ÷ 1000
For a 50ml measure at 20% ABV: 50 × 20 ÷ 1000 = 1 units.
Try the unit calculatorThe weekly guideline
The UK Chief Medical Officers advise no more than 14units a week for men and women alike, spread over three days or more, with several drink-free days. Drinking a week's worth in one session carries its own risks, separate from the weekly total.
If you drink heavily every day, stopping suddenly can be dangerous. Speak to your GP before cutting down sharply.
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