How much caffeine is in Espresso (single)?

A single shot of espresso delivers 63 milligrams of caffeine in a standard 30-millilitre (1-fluid-ounce) serving, according to analyses compiled by the USDA.

That 63 mg makes espresso one of the most caffeine-dense coffee beverages available: when scaled to 100 ml, the concentration reaches 210 mg per 100 ml. By comparison, a typical 240-ml mug of drip coffee (USDA-reported 96 mg) contains only about 40 mg per 100 ml. Because the volume is small, the total dose remains modest—roughly two-thirds of what you get from a full cup of filter coffee—yet the rapid extraction through a pressurised puck of finely ground coffee delivers the caffeine efficiently, so the onset of alertness often feels sharper. Peak plasma levels typically arrive between 30 and 60 minutes after ingestion.

How long Espresso (single) stays in your system

How long 63 mg stays in your system

Caffeine follows first-order elimination with a population-average half-life of 5.7 hours. That means your body clears half of the dose every 5.7 hours. For a 63-mg espresso, the arithmetic works out as: after 3 hours, remaining ≈ 63 × (0.5)^(3/5.7) ≈ 44 mg; after 6 hours, ≈ 30 mg; after 9 hours, ≈ 21 mg; and after 12 hours, ≈ 15 mg. So even a small shot leaves measurable amounts well into the afternoon and evening.

If you drink the espresso at 15:00, by 21:00—six hours later—circa 30 mg are still circulating. For most healthy adults that sub-50 mg level is not enough to block sleep onset entirely, but the 2013 study by Drake et al. (JCSM) demonstrated that even 400 mg consumed six hours before bedtime can cost more than an hour of total sleep. With a much smaller dose, the effect is proportionally milder, yet sensitive individuals, slow metabolisers, or those who already struggle with sleep may want to push the last shot earlier. Use our latest cup before bedtime tool to map your own cutoff time.

Sleep, limits, and the 63-mg shot

A single espresso’s 63-mg dose is small enough that, for most adults, one or two spaced through the morning won’t disturb sleep. Caffeine’s 5.7-hour half-life means if you drink one at 7:00, by 13:00 roughly 31.5 mg remain, and by 19:00 (12 hours later) about 15 mg linger—a level that seldom interferes with deep sleep. But timing matters more for repeated doses or for late shots. The seminal Drake et al. (2013) study showed that 400 mg taken even six hours before bedtime (i.e., at 17:00 for a 23:00 bedtime) significantly disrupted sleep. Scaled down, a 63-mg shot consumed at 17:00 would leave roughly 30 mg at 23:00—a fraction of the study dose, but potentially enough to shorten deep sleep in sensitive individuals or those who metabolise caffeine slowly.

For daily budgeting, the 400-mg upper limit recommended by both the FDA and the EFSA (European Food Safety Authority, 2015) allows about six single espressos. However, EFSA also advises that pregnant women should cap total daily caffeine at 200 mg—equivalent to about three single shots—and single doses should stay below 200 mg, which a single espresso easily respects. Adolescents, per Health Canada guidance often cited, should not exceed 100 mg per day, so a single 63-mg shot could be their entire allowance. Weight-adjusted safe doses range from 2.5 mg/kg to 6 mg/kg depending on sensitivity; a 70-kg adult at the lower end would have a personal limit of 175 mg, meaning only about 2.8 single espressos before reaching that threshold. Use our weight-based calculator to get your own number.

One more practical planning tool: if you aim to be caffeine-free by a 22:30 bedtime and are reasonably sensitive, a single espresso at 14:00 (eight hours’ gap) would leave around 23 mg at sleep time—likely acceptable for many. Plug your habits into the latest cup before bedtime tool to see when to have your last shot.

Espresso vs. other coffee drinks

At 63 mg, a single espresso sits near the lower end of coffee-shop beverages in total caffeine, though in concentration it out-paces almost everything except a pure ristretto. Among its espresso-based peers, the dose is identical to a traditional cappuccino (63 mg/180 ml), macchiato (63 mg/60 ml), and ristretto (63 mg/20 ml)—all built on a single shot. Drinks that use a double shot naturally double the number: a double espresso, americano, and large two-shot latte each deliver 126 mg. A cortado, often made with a single shot but sometimes with a double, averages 79 mg in our dataset, while a mocha (240 ml) typically contains 95 mg thanks to the added chocolate.

Against non-espresso benchmarks, the single shot is a lighter lift than an 8-oz (240-ml) drip coffee, which averages 96 mg—about 1.5 times more. It holds less caffeine than a 250-ml can of Red Bull (80 mg) and far less than a 473-ml can of Monster Energy (160 mg). On the other end, green tea (240 ml) brings just 28 mg, and a 355-ml Coca-Cola Zero Sugar has 34 mg. So the single espresso lands in the middle: a moderate dose that provides a noticeable boost without approaching most people’s daily limit in one go. If you want to stack drinks visually, try our side-by-side drink comparison tool.

The 63-mg shot represents about 16% of the FDA’s 400-mg daily guidance for healthy adults, meaning six single espressos would total 378 mg—perilously close to the ceiling. In practice, most people order double shots, so two doubles already reach 252 mg, leaving little room for later caffeine. Understanding where each drink sits relative to the limit is the purpose of our safe daily limit by body weight calculator.

What changes the number for Espresso (single)

What changes the caffeine in your espresso

No two espresso shots are identical. The 63-mg figure is a representative value from the USDA FoodData Central database for a commercially prepared 30-ml single espresso, but real-world pours can range from roughly 50 mg to 75 mg depending on several variables.

The biggest lever is the coffee itself. Coffea arabica beans, which dominate specialty coffee, contain roughly half the caffeine of Coffea canephora (robusta). A blend that incorporates robusta will push the number higher. Roast degree also introduces nuance: per bean, darker roasts lose a small amount of caffeine, but the light-roast bean is denser; when you measure by scoop rather than weight, light roasts can deliver more caffeine. For espresso, the dose is almost always weighed (typically 7–9 grams for a single), so roast level’s impact on caffeine remains modest—generally within a few milligrams.

Extraction parameters add further spread: grind size, water temperature (90–96 °C), pressure (9 bars is typical), and contact time (20–30 seconds) all influence how efficiently caffeine is dissolved. A ristretto—cutting the extraction short at about 15–20 ml—often yields a similar or only slightly lower caffeine load because most of the caffeine extracts early; our dataset lists 63 mg for a 20-ml ristretto too. In contrast, a lungo, where water continues to flow beyond the standard volume, may extract more caffeine from the same coffee dose, sometimes reaching 80–85 mg.

Commercial chains often quote higher numbers: Starbucks reports 75 mg for a solo shot, while other roasters may state 70–85 mg. Decaf espresso is not caffeine-free: a single decaf shot typically holds 3–15 mg. All of this variation is why we treat any single number as a best-estimate starting point.

Where this figure comes from

Where the 63-mg figure comes from

The 63-milligram value is drawn from the USDA FoodData Central entry for a 1-fluid-ounce (30-ml) espresso. The USDA compiles data from multiple validated analytical sources and reports an average that reflects chain-coffee samples as well as independent café pulls. Because caffeine content in a single shot varies with bean choice, grind, dose, and machine parameters, published numbers can differ: the Mayo Clinic caffeine chart gives a range of 60–72 mg per shot, while Starbucks’ own nutrition information states 75 mg for a solo. Our page relies on the USDA because it is the most transparent, regularly updated, and publicly accessible database covering a cross-section of the market.

When new, well-sampled data emerge—such as a large multi-city survey or an updated USDA release—we review and adjust the displayed number. The FDA’s consumer guidance of 400 mg/day provides the safety frame, but it does not prescribe per-drink figures. We also cross-reference with EFSA’s 2015 opinion, which underpins the pregnancy and single-dose cautions used throughout the site. By being explicit about our source and the inherent spread, we aim to give you a number you can trust while acknowledging the real-world range.

Bottom line

Bottom line

A single 30-ml espresso shot contains 63 mg of caffeine. That is about two-thirds the caffeine of an 8-oz mug of drip coffee (96 mg) and 16% of the 400-mg FDA daily guidance for healthy adults. Caffeine from this dose halves roughly every 5.7 hours: after six hours you still have about 30 mg in your system. For most people, one or two single shots early in the day pose little risk to sleep, but if you are pregnant, an adolescent, or sensitive to caffeine, even 63 mg may be a meaningful fraction of your personal limit. Always check total intake from all sources and use the caffeine half-life calculator to map your day.