Coffee Drink

Espresso: Shot Size, Caffeine and a Simple Recipe

By Jason HarrisReviewed by Online Coffee Guide editorial teamPublished June 24, 2026Updated October 1, 20267 min read

Espresso is concentrated coffee brewed by forcing hot water through finely ground coffee under pressure. It names a brewing method and the resulting drink, not a particular bean or roast.

Fresh espresso with golden crema in a white ceramic cup beside an espresso machine.

Drink Snapshot

Caffeine: ~75 mg referenceGeneric USDA espresso, 36 gGeneric prepared-espresso estimate for the stated mass.
Calories: About 3 kcalPlain 36 g espresso estimateBefore sugar, milk, syrup or cream.

Serving, sugar and sources

Serving: 1 home double, 36 g brewed espresso
Made with: 18 g ground coffee → 36 g brewed espresso
Sugar: 0 g reference. Plain espresso; no added sugar.
Preparation: About 3 minutes with the machine ready

Calculated from generic USDA restaurant-prepared espresso. Crema makes volume variable; a 36 g double is not two 1 fl oz nutrition servings. See the full calculation or label comparison.

Key Takeaways

1Our home double starts with 18 g dry coffee and yields 36 g espresso: a 1:2 ratio by mass.
2A generic 1 US fl oz espresso reference has about 63 mg caffeine.
3Plain espresso has very few calories; crema thickness and a strong taste do not tell you its caffeine content.

On This Page11 Sections

What Actually Defines Espresso?

Espresso is both a pressure-brewing method and the small, concentrated coffee it produces. It is usually served on its own in a demitasse or used as the base of a milk or water drink. The National Coffee Association makes the key distinction: espresso is not a bean variety or a roast level.

Arabica, robusta, blends and single-origin coffees can all be brewed this way. A bag labeled “espresso roast” suggests the roaster has chosen a roast or blend for that use; it does not mean the beans came from an espresso plant.

This page explains the drink and its serving sizes. For equipment and extraction detail, use the espresso brewing-method guide; for a learning sequence, start with the espresso beginner roadmap.

How Big Is an Espresso Shot?

The Italian Espresso Institute describes its certified espresso as about 25 ml (0.8 US fl oz). A modern double may instead be specified by the weight of coffee in the basket and the weight of the drink in the cup. Ask which serving convention is being used. “One shot” is not a reliable universal measurement.

Espresso shot-size infographic separating an approximately 25 ml Italian serving, an 18 g to 36 g home double, and a 63 mg per fluid ounce caffeine reference — The home recipe is measured by mass; the caffeine figure belongs to a separate generic reference serving. Portions are not to scale.

How big is an espresso shot?

How big is an espresso shot?
Reference	Amount	What it tells you
Certified Italian espresso	About 25 ml (0.8 US fl oz)	A particular serving tradition and specification
This home double	18 g dry coffee → 36 g espresso	A repeatable 1:2 recipe by mass
Generic caffeine serving	1 US fl oz	The serving attached to the commonly quoted 63 mg reference
A café's “shot”	Ask for its dose and yield	The actual recipe being served

The SCA's report on a 2017 barista survey illustrates why these distinctions matter: 93% of respondents called their espresso a double, and 82% measured output by weight. The average yield was 36.5 g. This was a 275-person survey with mostly US respondents, not a worldwide rule or a current census.

Why Grams and Milliliters Are Not Interchangeable

Crema contains gas and settles over time, changing a shot's visible volume. A scale gives a more repeatable recipe measurement. A 36 g double is therefore not automatically two 1 US fl oz servings. Nor does the capacity of a 90 ml (3 US fl oz) cup tell you how much espresso is inside it.

How Much Caffeine Is in Espresso?

The generic caffeine reference is about 63 mg per 1 US fl oz. For the 36 g home recipe, scaling USDA's generic restaurant-prepared espresso record gives an estimated 75 mg.

How much caffeine is in espresso?

How much caffeine is in espresso?
Clearly defined reference	Caffeine
Generic espresso, 1 US fl oz	About 63 mg
Two equivalent 1 US fl oz reference servings	About 126 mg by arithmetic
Generic USDA espresso, scaled to 36 g	About 75 mg
Your own 18 g → 36 g extraction	Depends on the beans, dose and extraction

Use the seller's measured product information when a particular amount matters.

How the references are calculated, and why shots vary

The USDA record contains 212 mg caffeine per 100 g prepared espresso: 212 × 36 ÷ 100 = 76.32 mg, rounded to about 75 mg. Its energy value is 9 kcal per 100 g, giving 9 × 36 ÷ 100 = 3.24 kcal, rounded to 3. It lists 0 g sugar. These figures describe a generic prepared beverage, not a measured 18 g-in/36 g-out extraction.

A 2007 study of 97 retail espressos on Australia's Gold Coast found 25–214 mg per serving, with a mean of 106 mg. That historical sample shows why a fixed “mg per shot” claim can mislead; its range is not a forecast for every café.

Does Decaf Espresso Contain Caffeine?

Usually, yes. Mayo Clinic's reference chart lists about 1 mg for 1 US fl oz of decaf espresso. Decaf is not the same as caffeine-free, and recipes and products differ.

How Many Calories Are in Espresso?

The plain 36 g espresso is about 3 calories, with 0 g sugar in the generic reference. Milk and sweeteners add their own nutrients; the estimates above cover only the black espresso.

How many calories are in espresso?

How many calories are in espresso?
Addition to the plain espresso	Effect on the serving
Water or ice	Dilutes concentration without adding sugar or meaningful calories
Milk	Adds calories and naturally occurring milk sugar
Sugar, syrup or sweetened sauce	Adds calories and sugar according to the portion
Cream	Adds calories and fat according to the portion

The nutrition estimate is for the brewed beverage, not the 18 g of dry grounds left in the portafilter. A latte or mocha needs its own ingredient calculation.

Measured Espresso Recipe

Recipe

Measured double espresso

Makes:: 1 serving
Time:: About 3 minutes once the machine is ready

Ingredients

18 g coffee beans, finely ground for espresso
Water suitable for your machine, enough to produce 36 g brewed espresso

Equipment

Espresso machine with a suitable double basket
espresso grinder
scales
tamper
60–90 ml (2–3 US fl oz) cup

Method

Prepare the basket. With the machine warmed, grind 18 g coffee into a clean, dry double basket suited to that dose. Distribute evenly and tamp level.
Weigh the output. Lock in the portafilter. Place a warmed 60–90 ml (2–3 US fl oz) cup on the scales and tare to zero. Start brewing and aim to stop at 36 g total espresso, including both streams from a spouted portafilter.
Taste and adjust. Record the shot time; around 25–30 seconds is a useful initial observation, not a requirement. Stir, let the espresso cool enough to sip, and taste. Adjust grind or yield for the next shot, changing one variable at a time.

Estimated nutrition per serving: 3 calories; total sugar 0 g. Serving: 1 double espresso, 36 g brewed beverage.

Recipe notes

Allow additional time to warm the machine according to its manual. Use a dose suited to your basket.

Start at a 1:2 yield. Record shot time, taste, and adjust one variable.

Nutrition estimates use generic prepared-espresso data.

Cup: 60–90 ml (2–3 US fl oz) capacity.

What does 1:2 mean? Divide the brewed beverage mass by the dry coffee dose: 36 ÷ 18 = 2. This is coffee grounds to finished espresso, not grounds to the water in the machine's tank. Breville's espresso recipe also uses a mass-based double-shot starting point and emphasizes adjusting for the beans.

Hands holding an espresso portafilter while pressing a level tamper into the coffee bed — Keep puck preparation consistent so a change in grind or yield is easier to evaluate.

For equipment and extraction technique, use the espresso brewing method. For a full setup and dialing sequence, continue to how to make espresso at home or the espresso ratio guide and calculator.

What Does Espresso Taste Like?

Espresso concentrates a coffee's acidity, sweetness, bitterness and aroma into a small serving. Roast, origin, extraction and temperature all affect the result. Chocolate, nuts or fruit may describe a coffee's flavor.

Use this as an initial troubleshooting guide, then follow the espresso dial-in guide for a fuller diagnosis.

What does espresso taste like?

What does espresso taste like?
What you notice	First thing to check
Very fast flow with a thin, sharp result	Dose, basket fit and grind; a finer grind may help
Very slow flow with harsh or dry flavor	An overly fine grind, excess dose or uneven puck preparation
Sour and bitter patches in the same cup	Uneven flow or channeling; improve distribution before changing everything
A shot that tastes good outside the expected time	Keep the successful recipe; seconds are evidence, not a taste score

What Is Crema?

Crema is the transient foam on espresso, influenced by gases, liquid and particles in the brew. The Food Biophysics review of espresso foam explains its physical structure.

Crema catches my eye, but a thick layer doesn't tell me whether I'll enjoy the espresso. I look for sweetness in the liquid and a finish that doesn't turn dry; an attractive surface can't make up for a harsh sip.

Does Espresso Have More Caffeine Than Drip Coffee?

Per fluid ounce, the generic espresso reference is more concentrated. Per serving, the larger drip coffee can contain more total caffeine. For example, the NCA's espresso reference is about 63 mg in 1 US fl oz, while Mayo Clinic lists 96 mg in 8 US fl oz brewed coffee.

Espresso versus drip coffee caffeine comparison: about 63 mg per one-fluid-ounce espresso and about 96 mg per eight-fluid-ounce brewed coffee reference — NCA/USDA and Mayo Clinic caffeine estimates compare the two defined serving sizes.

Does espresso have more caffeine than drip coffee?

Does espresso have more caffeine than drip coffee?
Difference	Espresso	Drip or filter coffee
Brewing	Pressure through a fine coffee bed	Water passes through a filter and coffee bed
Usual format	Small, concentrated serving	Larger, more dilute serving
Texture	Often fuller, with crema	Usually clearer and lighter
Caffeine comparison	Check the whole serving	Check the whole serving

“Stronger” can mean a more intense taste, a higher concentration or more total caffeine. State which you mean. Drip coffee is a different brew, not espresso with water added.

Single, Doppio, Ristretto, Lungo, and Americano

These names change different parts of the order. A double can also be pulled short or long.

Single, doppio, ristretto, lungo, and Americano

Single, doppio, ristretto, lungo, and Americano
Order	What changes	Useful question at the café
Single espresso	A nominal single portion	Is this a dedicated single basket or a split double?
Doppio	A double espresso portion	Is a double already your default shot?
Ristretto	Shorter yield relative to the coffee dose	What dose and yield do you use?
Lungo	Longer extraction through the coffee	Is this extracted longer or diluted afterward?
Americano	Espresso combined with added water	How many shots and how much water?
Long black	Usually espresso added to hot water	What is your cup size and shot recipe?

Espresso as the Base of Other Drinks

If you want a little milk, try an espresso macchiato. For more milk in a small drink, compare a cortado and piccolo latte. A latte is more milk-forward; a cappuccino adds a more prominent foamed texture. A mocha includes chocolate.

The amount of espresso matters more for caffeine than whether the menu name includes milk.

Common Espresso Questions

How do you pronounce espresso?

Say eh-SPRESS-oh. Espresso is the usual spelling on coffee menus; it names the pressure-brewed coffee described here.

Can you make espresso without an espresso machine?

A moka pot, AeroPress or strong instant coffee can give you a concentrated base for a milk drink, but they do not reproduce the same espresso process. Some manual devices can produce espresso pressure; follow the device's recipe.

Do you need special espresso beans?

No single bean or roast is mandatory. An espresso-labeled blend can be a convenient starting point, but choose a coffee you enjoy and adjust the recipe to it.

Is a double espresso two shots?

Doppio means a double serving, but many cafés already use a double basket as their default shot. Ask about the dose and total output before ordering two shots.

Can you drink espresso with sugar?

Yes. Sugar is optional; the plain-coffee calorie and sugar estimates on this page do not include it.