Caffeine in drinks
How much caffeine is in Instant coffee?
Data checked against the source on 2026-10-03 by Oleksii Y.
One 8 fl oz cup (240 g) of Instant coffee has 62.4 mg of caffeine, according to USDA Agricultural Research Service, FoodData Central (FNDDS).
How Instant coffee compares
- Strength: 26 mg per 100 ml.
- One 8 fl oz cup (240 g) has as much caffeine as about three quarters of a cup of brewed coffee, which has 94.8 mg per 8 fl oz cup.
- Of the 13 other coffee drinks in our coffee chart, 9 have more caffeine per serving and 3 have less.
How much will be left at bedtime?
1 × 8 fl oz cup (240 g) of Instant coffee
Left at 11:00 PM (8 h later), average metabolism
≈ 20 mg
Range 10–31 mg (fast to slow metabolism)
To be at 50 mg or less by bedtime, have 62 mg by 8:42 PM (average) or 7:46 PM (slow metabolism).
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
Caffeine by size
| Serving | Caffeine |
|---|---|
| 8 fl oz cup (240 g) | 62.4 mg |
| 6 fl oz serving (179 g) | 46.5 mg |
How long does Instant coffee 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 cup (240 g) of Instant coffee (62 mg), about 31 mg is still in your body 5 hours later and about 16 mg after 10 hours. If you clear caffeine slowly (an 8-hour half-life), about 26 mg is left after 10 hours.
Estimated caffeine left at 11:00 PM from one 8 fl oz cup (240 g) (62 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) | ≈ 8 mg | 2–17 mg |
| 12:00 PM (11 h before bed) | ≈ 13 mg | 5–24 mg |
| 3:00 PM (8 h before bed) | ≈ 20 mg | 10–31 mg |
| 6:00 PM (5 h before bed) | ≈ 31 mg | 20–40 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 6 servings.
- Up to 200 mg at one time for healthy adults (EFSA): about 3 servings in one go.
- Up to 200 mg a day in pregnancy (EFSA, NHS): about 3 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
USDA lists 3,140 mg of caffeine per 100 g of instant coffee powder, about 31 mg per gram, so the amount of powder sets the dose.
How the serving amount was worked out: USDA lists 26 mg per 100 g of prepared instant coffee in both records; 240 g × 0.26 = 62.4 mg (FDC 2710449); 179 g × 0.26 = 46.5 mg (FDC 174130).
Instant coffee vs other coffee drinks
- Brewed coffee: Instant coffee has less caffeine than brewed coffee per 8 fl oz cup (240 g): 62.4 mg vs 94.8 mg.
- Iced coffee: Instant coffee has less caffeine than iced coffee per 8 fl oz cup (240 g): 62.4 mg vs 74.4 mg.
- Cold brew coffee: Instant coffee has less caffeine than cold brew coffee per 8 fl oz cup (240 g): 62.4 mg vs 234.6–291.5 mg.
Common questions
How much caffeine is in Instant coffee?
USDA Agricultural Research Service, FoodData Central (FNDDS) gives 62.4 mg of caffeine per 8 fl oz cup (240 g). Other sizes are in the table on this page.
How many Instant coffee 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 62.4 mg per 8 fl oz cup (240 g), that is about 6 servings if Instant coffee is your only source. In pregnancy the reference is 200 mg a day.
How late can I drink Instant coffee?
With an 11:00 PM bedtime, our model suggests having one serving by about 8:42 PM for average metabolism, or 7:46 PM if you clear caffeine slowly. This is an estimate, not a rule.
Does Instant coffee have more caffeine than Brewed coffee?
Instant coffee has less caffeine than brewed coffee per 8 fl oz cup (240 g): 62.4 mg vs 94.8 mg.
How long does Instant coffee stay in your system?
Of the 62 mg in one 8 fl oz cup (240 g), roughly 31 mg remains after 5 hours and 16 mg after 10 hours with our average 5-hour half-life. From fast to slow metabolism, 10 hours later it is between 6 and 26 mg.
Where the number comes from
- Coffee, instant, reconstituted. USDA Agricultural Research Service, FoodData Central (FNDDS). FDC ID 2710449, nutrient "Caffeine" (262): portion "1 cup (8 fl oz)" = 240 g. Accessed 2026-10-02. Source ↗
- Beverages, coffee, instant, regular, prepared with water. USDA Agricultural Research Service, FoodData Central (SR Legacy). FDC ID 174130, nutrient "Caffeine" (262): portion "1 serving 6 fl oz" = 179 g. Accessed 2026-10-02. Source ↗
- Beverages, coffee, instant, regular, powder. USDA Agricultural Research Service, FoodData Central (SR Legacy). FDC ID 171893, nutrient "Caffeine" (262): 3140 mg per 100 g, 15 samples. 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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