Diet Coke contains caffeine, though a relatively moderate amount compared to coffee or energy drinks. Here are some details on the caffeine amount in Diet Coke:

• A 12 fl oz (355 ml) can of Diet Coke contains 46 mg of caffeine.
• A 20 fl oz (591 ml) bottle of Diet Coke contains 76 mg of caffeine.
• For comparison, an 8 oz cup of brewed coffee can contain around 95-165 mg caffeine.

So a standard 12 oz can of Diet Coke has about a third to half the caffeine of an 8 oz coffee. The caffeine levels can vary slightly in different markets, but generally fall into the 30-50 mg range per 12 oz serving.

It’s worth noting that while 46 mg of caffeine is a moderate amount, intake can add up quickly if someone drinks multiple Diet Cokes per day. Health authorities generally recommend limiting caffeine intake to no more than 400 mg per day for healthy adults.

The caffeine in Diet Coke comes from the original cola recipe, as caffeine is a typical ingredient in most cola beverages, diet or regular. But Diet Coke gets its flavoring from non-nutritive sweeteners instead of sugar.