Caffeine in drinks
How much caffeine is in White tea?
Data checked against the source on 2026-10-03 by Oleksii Y.
One 6 fl oz cup of White tea has 15–20 mg of caffeine, according to Center for Science in the Public Interest.
How White tea compares
- Strength: 9.9 mg per 100 ml (middle of the range).
- One 6 fl oz cup has as much caffeine as about a quarter to a third of a cup of brewed coffee, which has 94.8 mg per 8 fl oz cup.
- Of the 17 other teas in our tea chart, 12 have more caffeine per serving and 5 have less.
How much will be left at bedtime?
1 × 6 fl oz cup of White tea (middle of the range)
Left at 11:00 PM (8 h later), average metabolism
≈ 6 mg
Range 3–9 mg (fast to slow metabolism)
18 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 White tea 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 6 fl oz cup of White tea (18 mg), about 9 mg is still in your body 5 hours later and about 5 mg after 10 hours. If you clear caffeine slowly (an 8-hour half-life), about 8 mg is left after 10 hours.
Estimated caffeine left at 11:00 PM from one 6 fl oz cup (18 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) | ≈ 2 mg | 1–5 mg |
| 12:00 PM (11 h before bed) | ≈ 4 mg | 1–7 mg |
| 3:00 PM (8 h before bed) | ≈ 6 mg | 3–9 mg |
| 6:00 PM (5 h before bed) | ≈ 9 mg | 6–12 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 20 servings.
- Up to 200 mg at one time for healthy adults (EFSA): about 10 servings in one go.
- Up to 200 mg a day in pregnancy (EFSA, NHS): about 10 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
In a lab study, white, green and black teas ranged from 14 to 61 mg per serving, with no observable trend by type of tea.
White tea vs other tea drinks
- Black tea: White tea has less caffeine than black tea per 6 fl oz cup: 15–20 mg vs 35.6 mg.
- Green tea: White tea has less caffeine than green tea per typical serving. White tea: 15–20 mg per 6 fl oz cup; Green tea: 29.4 mg per 1 cup (245 g).
- Oolong tea: White tea has less caffeine than oolong tea per typical serving. White tea: 15–20 mg per 6 fl oz cup; Oolong tea: 38.4 mg per 1 cup (240 g).
Common questions
How much caffeine is in White tea?
Center for Science in the Public Interest gives 15–20 mg of caffeine per 6 fl oz cup.
How many White tea 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 15–20 mg per 6 fl oz cup, that is about 20 servings if White tea is your only source. In pregnancy the reference is 200 mg a day.
How late can I drink White tea?
One serving has about 18 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.
Does White tea have more caffeine than Black tea?
White tea has less caffeine than black tea per 6 fl oz cup: 15–20 mg vs 35.6 mg.
How long does White tea stay in your system?
Of the 18 mg in one 6 fl oz cup, roughly 9 mg remains after 5 hours and 5 mg after 10 hours with our average 5-hour half-life. From fast to slow metabolism, 10 hours later it is between 2 and 8 mg.
Where the number comes from
- Caffeine chart. Center for Science in the Public Interest. row "White tea, most brands | 6 oz. | 15–20" Accessed 2026-10-02. Source ↗
- Caffeine content of brewed teas. Journal of Analytical Toxicology. PMID 19007524, abstract. 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 ↗
An app for better sleep is on the way
We’re working on a mobile app to help you sleep better. It isn’t out yet. Leave your email and we’ll let you know when it launches.