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How Much Caffeine is in Diet Pepsi?

Diet Pepsi

Caffeine (serving: 12 fl oz)
35 mg
Caffeine (mg / fl oz)
Caffeine strength

Diet Pepsi is the sugar-free version of Pepsi cola soda, a huge competitor in the soda industry. Diet sodas and sugar-free drinks are always popular beverages, especially for those who can’t have sugar in their diets. But is diet Pepsi caffeinated like the original? How much caffeine is actually in a diet Pepsi? You can expect about 35 mg of caffeine in a 12-ounce bottle of Diet Pepsi. Let’s take a closer look at the cola giant’s diet soda to see how much caffeine it contains:

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How Much Caffeine does Diet Pepsi Contain?

Diet Pepsi may not contain sugar, but it still has caffeine in it. One 12oz bottle of Diet Pepsi contains 36.7mg of caffeine, which is a similar amount to other colas. Since the focus is on removing the sugar, Diet Pepsi tries to keep the flavors and caffeine amounts identical to the original. However, the flavor is noticeably different due to the aspartame’s flavor.

While it’s not a lot of caffeine, drinking lots of soda with caffeine daily is not a good habit to form. The caffeine in Diet Pepsi is synthetic, unlike the natural caffeine content of coffee. Soda, in general, is simply not a good choice for your daily pick-me-up, even if it’s the diet version of your favorite cola. The only benefit is the lack of sugar, thanks to the ultra-sweet and calorie-free properties of aspartame.

can of diet pepsi on table
Image credit: Unsplash

Caffeine Comparison

Here’s a comparison of caffeine content between diet Pepsi and other caffeinated drinks:

Diet Pepsi vs. Pepsi

Diet Pepsi: 36.7mg per 12oz
Pepsi: 38.9mg per 12 oz

Diet Pepsi may not have all the sugar that the original Pepsi has, but it has almost the same caffeine content. You won’t notice the 2.2mg difference, but the flavor of Diet Pepsi is different than the original.

Diet Pepsi vs. Diet Coke

Diet Pepsi: 36.7mg per 12oz
Diet Coke: 46mg caffeine per 12oz

The two cola giants may battle it out over many things, but the diet version of Coca-Cola edges diet Pepsi out in terms of caffeine. While it’s not a lot of caffeine, it’s enough to make some people reach for a diet coke instead.

Diet Pepsi vs. Coffee

Diet Pepsi: 36.7mg per 12oz
Coffee: 95mg per 12oz

Coffee is a highly caffeinated drink, especially compared to most sodas. Diet Pepsi is less than half of the coffee’s caffeine content while also loaded with artificial chemicals that black coffee doesn’t contain.

Arizona Green Tea
Image Credit: Connor Dickson, Unsplash

Diet Pepsi vs. Arizona Diet Green Tea

Diet Pepsi: 36.7mg per 12oz
Arizona Diet Green Tea: 15mg per 12oz

Tea is a naturally caffeinated drink, but it’s not necessarily strong. Diet Pepsi has more caffeine than Arizona Diet Green Tea, so you may notice a difference if you try tea instead of soda.

Diet Pepsi vs. Pepsi Zero

Diet Pepsi: 36.7mg per 12oz
Pepsi Zero: 69mg per 12oz

When it comes to Pepsi’s sugar-free sodas, Pepsi Zero has a huge lead in terms of caffeine content. It’s got almost as much caffeine as coffee, which is surprisingly high for a soda.

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What is Diet Pepsi, and is it Healthy or Safe to Drink?

Diet Pepsi is the non-sugar version of Pepsi Cola, a popular soft drink brand that has over 40g of sugar per 12oz serving. Diet Pepsi contains aspartame, an artificial sweetener that makes it a calorie-free beverage. While there are thousands of studies and arguments that aspartame is safe, there are just as many that claim it is not safe to consume regularly.

coke coffee
Image credit: PxHere

Non-Soda Alternatives to Diet Pepsi

  • Coffee – Coffee is a definite upgrade, both for health and caffeine. It’s a super low-calorie drink, especially if you drink it black. Be wary of flavored creamers and drinks at coffee shops, which usually contain a lot of sugar.
  • Green or Black Tea – Part of becoming healthier is trimming down the chemicals you consume, especially artificial dyes and flavors. If you’re adamant about having energy drinks in your life, Celsius is a good choice to avoid unnecessary chemicals.
  • Celsius Energy – If you’re drinking Diet Pepsi as a low-calorie caffeine source, consider switching to Celsius Energy. It’s got no artificial ingredients like food dye or added sugar, but it also doesn’t contain the artificial sweeteners that Diet Pepsi has. Celsius Energy has 200mg of caffeine, so it’s got a serious kick to it.

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Part of living a healthy lifestyle or dieting is cutting out artificial ingredients completely, so “diet” sodas aren’t the best choice. Aspartame in high doses can cause digestive issues, which can lead to cramps, bloating, and intestinal pain. If you’re drinking Diet Pepsi for the caffeine, consider switching to a different source that doesn’t contain artificial ingredients or sugar.

See Also: How Much Caffeine Is In Pepsi Max?


Jaimie Wisniowski

Jaimie is a freelance writer fueled by coffee, whether it’s hot, iced, or made from a local coffee shop. She enjoys writing all things coffee, especially if it means trying the latest coffee shop trends (hello cold foam!). After spending years writing poems, college essays, and short stories, it only a matter of time to turn writing into a career. Writing about coffee simply combined two of her favorite things! When she’s not drinking coffee by the minute and writing at her laptop, Jaimie spends time hiking, exercising, and living an active life. She also loves to snuggle up with a good book and her dog, Margo. If you catch her without a cup of coffee, she’s probably on her way to the coffee maker now.

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