Caffeine & Sleep
Soda

Caffeine in Diet Pepsi

35mg
per 12 oz
9% of FDA daily max

Is that a lot?

Diet Pepsi is 9% of the FDA’s recommended daily maximum, in a single 12 oz.

Green tea
28 mg
Diet Pepsi
35 mg
Espresso
63 mg
Red Bull
80 mg
Coffee
95 mg
FDA daily max · 400mg
Before bed

When can I drink Diet Pepsi and still sleep?

Your Diet Pepsi cutoff
You drink it at
Bedtime
Diet Pepsi · 35 mg · assuming an average ~5 h half-life
At bedtime
12 mg
close to optimal
Latest safe Diet Pepsi: 11:00 PM

How much caffeine is in Diet Pepsi?

Diet Pepsi carries about 35 mg of caffeine in a 12 oz can, a third of a coffee's load and milder than its zero-sugar cousin. Sugar-free, it offers just a gentle nudge of stimulation.

ServingCaffeineSugar
12 oz35 mg0 g

Will Diet Pepsi affect your sleep?

At 35 mg, Diet Pepsi starts below the 50 mg threshold and clears within a couple of hours. The caffeine is light enough that an evening can rarely interferes with sleep.

Source: PepsiCo product facts

Related drinks

Diet Pepsi & sleep — FAQ

Unlikely, with about 35 mg per can Diet Pepsi sits under the 50 mg threshold, so it shouldn't keep most people up at night.

Diet Pepsi has 35 mg per 12 oz — about 9% of the FDA’s 400 mg daily maximum for healthy adults.

It depends on your bedtime and how fast you clear caffeine. Use the calculator above to see when Diet Pepsi drops below the ~50 mg “ok to sleep” threshold for your bedtime.

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