Caffeine in drinks
How much caffeine is in Instant tea?
Data checked against the source on 2026-10-03 by Oleksii Y.
One 8 fl oz serving (238 g) of Instant tea has 26.2 mg of caffeine, according to USDA Agricultural Research Service, FoodData Central (SR Legacy).
How Instant tea compares
- Strength: 11 mg per 100 ml.
- One 8 fl oz serving (238 g) 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, 10 have more caffeine per serving and 7 have less.
How much will be left at bedtime?
1 × 8 fl oz serving (238 g) of Instant tea
Left at 11:00 PM (8 h later), average metabolism
≈ 9 mg
Range 4–13 mg (fast to slow metabolism)
26 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 Instant 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 8 fl oz serving (238 g) of Instant tea (26 mg), about 13 mg is still in your body 5 hours later and about 7 mg after 10 hours. If you clear caffeine slowly (an 8-hour half-life), about 11 mg is left after 10 hours.
Estimated caffeine left at 11:00 PM from one 8 fl oz serving (238 g) (26 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) | ≈ 3 mg | 1–7 mg |
| 12:00 PM (11 h before bed) | ≈ 6 mg | 2–10 mg |
| 3:00 PM (8 h before bed) | ≈ 9 mg | 4–13 mg |
| 6:00 PM (5 h before bed) | ≈ 13 mg | 8–17 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 15 servings.
- Up to 200 mg at one time for healthy adults (EFSA): about 7 servings in one go.
- Up to 200 mg a day in pregnancy (EFSA, NHS): about 7 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
Health Canada lists 15 mg of caffeine for a 237 ml cup of instant tea.
How the serving amount was worked out: USDA lists 11 mg per 100 g of prepared instant tea; 238 g × 0.11 = 26.2 mg.
Instant tea vs other flavored bottled tea drinks
- AriZona Green Tea: Instant tea has more caffeine than AriZona Green Tea per 100 ml (11 vs 2.5 mg). Instant tea: 26.2 mg per 8 fl oz serving (238 g); AriZona Green Tea: 15–18 mg per 22 oz can.
- Brisk Lemon Iced Tea: Instant tea has more caffeine than Brisk Lemon Iced Tea per 100 ml (11 vs 3.1 mg). Instant tea: 26.2 mg per 8 fl oz serving (238 g); Brisk Lemon Iced Tea: 11 mg per 12 fl oz can.
- Snapple Peach Tea: Instant tea has more caffeine than Snapple Peach Tea per 100 ml (11 vs 7.8 mg). Instant tea: 26.2 mg per 8 fl oz serving (238 g); Snapple Peach Tea: 37 mg per 16 fl oz bottle. Per serving the order flips, because the servings differ in size.
Common questions
How much caffeine is in Instant tea?
USDA Agricultural Research Service, FoodData Central (SR Legacy) gives 26.2 mg of caffeine per 8 fl oz serving (238 g).
How many Instant 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 26.2 mg per 8 fl oz serving (238 g), that is about 15 servings if Instant tea is your only source. In pregnancy the reference is 200 mg a day.
How late can I drink Instant tea?
One serving has about 26 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 Instant tea have more caffeine than AriZona Green Tea?
Instant tea has more caffeine than AriZona Green Tea per 100 ml (11 vs 2.5 mg). Instant tea: 26.2 mg per 8 fl oz serving (238 g); AriZona Green Tea: 15–18 mg per 22 oz can.
How long does Instant tea stay in your system?
Of the 26 mg in one 8 fl oz serving (238 g), roughly 13 mg remains after 5 hours and 7 mg after 10 hours with our average 5-hour half-life. From fast to slow metabolism, 10 hours later it is between 3 and 11 mg.
Where the number comes from
- Beverages, tea, instant, unsweetened, prepared with water. USDA Agricultural Research Service, FoodData Central (SR Legacy). FDC ID 174873, nutrient "Caffeine" (262): portion "1 serving 8 fl oz" = 238 g. Accessed 2026-10-02. Source ↗
- Caffeine in foods. Health Canada. Table 2 "Average amounts of caffeine in food and drink", row "Instant | 8 oz | 237 ml | 15 mg" (tea). 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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