The typical alcohol content of triple sec is 30 percent, with a variation between 15 and 40 percent depending on the brand. Two of the most popular brands, Cointreau and Grand Marnier, both have alcohol contents of 40 percent.
Triple sec, an orange-flavoured liqueur typically used as a flavouring agent for a variety of cocktails, comes in both alcoholic and non-alcoholic forms. Triple secs containing alcohol are derived from Cognac or brandy and can make up to 20 percent of the ingredients in a given cocktail mix.
The alcohol content of any liqueur can be described by percent alcohol by volume (ABV) or by proof. Proof is double the ABV, giving the typical proof of triple sec as 60.