Vodka and tonic is an alcoholic drink that is usually served in a tall highball style glass. Proportions of vodka and tonic used will vary according to taste and the total calorie content of the drink will fluctuate accordingly. Typically, consumers like to drink a vodka and tonic served over ice with a slice of lemon.
A serving of vodka consists of 1.5 ozs., according to the McKinley Health Center. The number of calories in a serving will depend on the alcoholic proof percentage of the vodka. An 80 percent proof serving has 97 calories, 90 percent proof vodka provides 110 and 100 percent proof brands contain 124 calories per serving.
One 8-oz. serving of tonic water has around 90 calories. Diet tonic water does not contain sugar and provides zero calories.
If you make a vodka and tonic with 100 percent proof vodka and add 8 ozs. of tonic, the drink will provide around 215 calories. If you use 80 percent proof vodka and diet tonic, you will ingest approximately 95 calories.