Caffeine in drinks
How much caffeine is in Decaf espresso?
Data checked against the source on 2026-10-03 by Oleksii Y.
One Single shot, 1 fl oz (29.6 g) of Decaf espresso has 0.3–15.8 mg of caffeine, according to USDA Agricultural Research Service, FoodData Central (SR Legacy).
How Decaf espresso compares
- Strength: 27 mg per 100 ml (middle of the range).
- One Single shot, 1 fl oz (29.6 g) has as much caffeine as less than a sixth 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, 12 have more caffeine per serving and 1 has less.
How much will be left at bedtime?
1 × Single shot, 1 fl oz (29.6 g) of Decaf espresso (middle of the range)
Left at 11:00 PM (8 h later), average metabolism
≈ 3 mg
Range 1–4 mg (fast to slow metabolism)
8 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 Decaf espresso 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 Single shot, 1 fl oz (29.6 g) of Decaf espresso (8 mg), about 4 mg is still in your body 5 hours later and about 2 mg after 10 hours. If you clear caffeine slowly (an 8-hour half-life), about 3 mg is left after 10 hours.
Estimated caffeine left at 11:00 PM from one Single shot, 1 fl oz (29.6 g) (8 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) | ≈ 1 mg | 0–2 mg |
| 12:00 PM (11 h before bed) | ≈ 2 mg | 1–3 mg |
| 3:00 PM (8 h before bed) | ≈ 3 mg | 1–4 mg |
| 6:00 PM (5 h before bed) | ≈ 4 mg | 3–5 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 25 servings.
- Up to 200 mg at one time for healthy adults (EFSA): about 12 servings in one go.
- Up to 200 mg a day in pregnancy (EFSA, NHS): about 12 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's decaf espresso value is derived from a similar food rather than measured, and it sits far below the only lab measurement found.
How the serving amount was worked out: Low end: USDA lists 1 mg per 100 g (derived from a similar food, not analysed); 29.6 g × 0.01 = 0.3 mg. High end: McCusker et al. (2006) measured 3.0 to 15.8 mg per shot in decaf espresso from one coffee chain (6 samples).
Decaf espresso vs other espresso drinks
- Espresso: Decaf espresso has less caffeine than espresso per Single shot, 1 fl oz (29.6 g): 0.3–15.8 mg vs 62.8 mg.
- Cuban coffee (cafecito): Decaf espresso has less caffeine than Cuban coffee (cafecito) per Single shot, 1 fl oz (29.6 g): 0.3–15.8 mg vs 61.7 mg.
Common questions
How much caffeine is in Decaf espresso?
USDA Agricultural Research Service, FoodData Central (SR Legacy) gives 0.3–15.8 mg of caffeine per Single shot, 1 fl oz (29.6 g).
How many Decaf espresso 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 0.3–15.8 mg per Single shot, 1 fl oz (29.6 g), that is about 25 servings if Decaf espresso is your only source. In pregnancy the reference is 200 mg a day.
How late can I drink Decaf espresso?
One serving has about 8 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 Decaf espresso have more caffeine than Espresso?
Decaf espresso has less caffeine than espresso per Single shot, 1 fl oz (29.6 g): 0.3–15.8 mg vs 62.8 mg.
How long does Decaf espresso stay in your system?
Of the 8 mg in one Single shot, 1 fl oz (29.6 g), roughly 4 mg remains after 5 hours and 2 mg after 10 hours with our average 5-hour half-life. From fast to slow metabolism, 10 hours later it is between 1 and 3 mg.
Where the number comes from
- Beverages, coffee, brewed, espresso, restaurant-prepared, decaffeinated. USDA Agricultural Research Service, FoodData Central (SR Legacy). FDC ID 174125, nutrient "Caffeine" (262): 1 mg per 100 g, derivation BFZN; portion "1 fl oz" = 29.6 g. Accessed 2026-10-02. Source ↗
- Caffeine content of decaffeinated coffee. Journal of Analytical Toxicology. PMID 17132260, abstract: "3.0-15.8 mg/shot" 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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