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 Canadian can of Diet Pepsi | |
| Product type | Diet cola |
|---|---|
| Owner | PepsiCo |
| Country | United States |
| Introduced | December 28, 1964 |
| Related brands | Pepsi One Pepsi Max Coca-Cola Zero Sugar Diet Coke |
| Website | pepsi.com/dietpepsi |
Diet Pepsi, currently stylised in all caps as Pepsi Diet, is a diet carbonated cola soft drink produced by PepsiCo, introduced in 1964 as a variant of Pepsi with no sugar. First test marketed in 1963 under the name Patio Diet Cola, it was re-branded as Diet Pepsi the following year, becoming the first diet cola to be distributed on a national scale in the United States. In the 1960s and 1970s, its competition consisted of the Coca-Cola Company's subsequently discontinued Tab. The United States represents the largest single market for Diet Pepsi.