On Numbeo, the metric used was “Restaurants: Domestic Beer, (0.5 liter draught)”. On Expatistan, it was “1 beer in neighbourhood pub (500ml or 1pt.)”. Where possible, the figures provided by both sites were averaged. Four cities had data on Numbeo, but not Expatistan, so the value from Numbeo was used alone. Similarly, 80 cities had data only on Expatistan, and that data was used alone.
The average price of $3.53 shown above is the mean of all the cities’ prices.