Supposedly there's a 32-year-old article with the secret formula.
Coca-Cola says the main ingredients used are no secret:
"The ingredients used in our beverages are listed on the product labels and many people have tried over time to crack the secret formula of Coca-Cola," said a spokesperson.
"That secret combination of ingredients holds a special place in the history and mythology of Coca-Cola – something we continue to celebrate as we mark our 125th anniversary this year."
See the "secret recipe" below
The secret recipe, which can only be mixed by two Coca-Cola executives in the world, reportedly contains the exact measures of all the different oils needed for Coca Cola’s secret ingredient, "Merchandise 7X".
Even though we are only talking about 1 per cent of the drink's total formula, Merchandise 7X is what gives the popular soft drink its unique taste.
Rumored to be under guard 24 hours a day in a vault, the official Coca-Cola recipe has been one of the most closely guarded trade secrets since the popular soft drink was concocted by medicinal chemist John Pemberton in 1886.
Okay, here it is, the not so secret recipe:
Citric acid: 3 oz (3 oz = 84.9 g)
Caffeine: 1 oz (1 oz = 28.3 g)
Sugar: 30 (unclear quantity, possibly pounds)
Water: 2.5 gallons (2.5 gal = 9.46 L)
Lime juice: 2 pints, 1 quart
Vanilla: 1 oz (1 oz = 28.3 g)
Caramel: 1.5 oz (1.5 oz = 42.5 g) or more to colour
Into every five gallons of syrup, add 2oz (2 oz = 56.6 g) of the following seven-part flavouring:
Alcohol: 8 oz (8 oz = 226 g)
Orange oil: 20 drops
Lemon oil: 30 drops
Nutmeg oil: 10 drops
Coriander oil : 5 drops
Neroli oil: 10 drops
Cinnamon oil: 10 drops
For your edifice: 1 dram = 3.55mL and 1mL = 20 drops.