Caffeine in drinks
How much caffeine is in Kombucha?
Data checked against the source on 2026-10-03 by Oleksii Y.
One 12 fl oz can or bottle (372 g) of Kombucha has 40.9 mg of caffeine, according to USDA Agricultural Research Service, FoodData Central (FNDDS).
How Kombucha compares
- Strength: 12 mg per 100 ml.
- One 12 fl oz can or bottle (372 g) has as much caffeine as about half a cup of brewed coffee, which has 94.8 mg per 8 fl oz cup.
- Of the 17 other teas in our tea chart, 5 have more caffeine per serving and 12 have less.
How much will be left at bedtime?
1 × 12 fl oz can or bottle (372 g) of Kombucha
Left at 11:00 PM (8 h later), average metabolism
≈ 14 mg
Range 6–21 mg (fast to slow metabolism)
41 mg is already at or under the 50 mg this tool aims to have left at bedtime.
What sleep studies found near this dose
- Gardiner et al. 2025 (randomized trial): In 23 healthy young men, 100 mg taken 12, 8 or 4 hours before bed had no significant effect on measured or self-rated sleep.
- Gardiner et al. 2023 (meta-analysis): To avoid losing sleep time, the authors suggest a coffee (107 mg per 250 ml) at least 8.8 hours before bed.
Estimate from a simple model: half-life of 3, 5 or 8 hours, 50 mg bedtime target. How we calculate
How long does Kombucha stay in your system?
Our model halves caffeine every 5 hours for average metabolism, and every 3 or 8 hours for fast or slow metabolism. From one 12 fl oz can or bottle (372 g) of Kombucha (41 mg), about 21 mg is still in your body 5 hours later and about 10 mg after 10 hours. If you clear caffeine slowly (an 8-hour half-life), about 17 mg is left after 10 hours.
Estimated caffeine left at 11:00 PM from one 12 fl oz can or bottle (372 g) (41 mg), using a half-life of 5 hours for average metabolism and 3 to 8 hours for the range. How we calculate
| Had at | Left at bedtime (average) | Range |
|---|---|---|
| 8:00 AM (15 h before bed) | ≈ 5 mg | 1–11 mg |
| 12:00 PM (11 h before bed) | ≈ 9 mg | 3–16 mg |
| 3:00 PM (8 h before bed) | ≈ 14 mg | 6–21 mg |
| 6:00 PM (5 h before bed) | ≈ 21 mg | 13–27 mg |
How many fit in a day?
Reference amounts are for caffeine from all sources combined. Counted at the upper end of the stated amount, one serving at a time:
- Up to 400 mg a day for most healthy adults (FDA, EFSA): about 9 servings.
- Up to 200 mg at one time for healthy adults (EFSA): about 4 servings in one go.
- Up to 200 mg a day in pregnancy (EFSA, NHS): about 4 servings.
These are reference amounts for groups of people, not a personal limit. Some people feel jittery or sleep worse on much less. See the cutoff calculator for timing.
Good to know
Labelled kombucha brands in CSPI's chart range from under 15 mg to 68 mg per bottle, mostly below USDA's tea-based estimate.
How the serving amount was worked out: USDA lists 11 mg per 100 g, modelled from its black and green tea ingredients rather than measured in kombucha; 372 g × 0.11 = 40.9 mg.
Common questions
How much caffeine is in Kombucha?
USDA Agricultural Research Service, FoodData Central (FNDDS) gives 40.9 mg of caffeine per 12 fl oz can or bottle (372 g).
How many Kombucha servings can I have in a day?
The FDA and EFSA cite up to 400 mg of caffeine a day, from all sources combined, for most healthy adults. At 40.9 mg per 12 fl oz can or bottle (372 g), that is about 9 servings if Kombucha is your only source. In pregnancy the reference is 200 mg a day.
How late can I drink Kombucha?
One serving has about 41 mg, which is at or under the 50 mg our calculator aims to have left at bedtime, so it sets no cutoff for a single serving. Several servings add up.
How long does Kombucha stay in your system?
Of the 41 mg in one 12 fl oz can or bottle (372 g), roughly 21 mg remains after 5 hours and 10 mg after 10 hours with our average 5-hour half-life. From fast to slow metabolism, 10 hours later it is between 4 and 17 mg.
Where the number comes from
- Tea, kombucha. USDA Agricultural Research Service, FoodData Central (FNDDS). FDC ID 2710509, nutrient "Caffeine" (262): portion "1 can or bottle (12 fl oz)" = 372 g; recipe ingredients. Accessed 2026-10-02. Source ↗
- Caffeine chart. Center for Science in the Public Interest. kombucha rows: Health-Ade 16 oz 5–15; Brew Dr. 14 oz less than 15; Synergy 16 oz 16–28; KeVita 15.2 oz 68. Accessed 2026-10-02. Source ↗
Recipes and labels change. If a number here no longer matches the label, the label wins.
General information, not medical advice
If you feel unwell after caffeine — for example chest pain, a fast or irregular heartbeat that does not settle, fainting, confusion or trouble breathing — get urgent medical help. If you are pregnant, take medication or have a heart, liver or anxiety condition, ask a doctor or pharmacist what amount is right for you.
Sources
- U.S. Food and Drug Administration (2024). Spilling the Beans: How Much Caffeine is Too Much? FDA Consumer Updates. fda.gov ↗
- European Food Safety Authority. Caffeine | EFSA. EFSA topic page (summary of the 2015 Scientific Opinion on the safety of caffeine). efsa.europa.eu ↗
- NHS. Foods to avoid in pregnancy. NHS. nhs.uk ↗
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