On especially trying mornings—Mondays, anyone?—you may find yourself substituting your regular cup of coffee for a shot or two of espresso. The rich, highly-concentrated brew has the reputation for being a real eye opener.

But is there really more caffeine in espresso than in a regularly brewed cup of java?

By the Numbers

Turns out, it depends on what you call a cup of coffee. An ounce—or one shot—of espresso has 63 milligrams (mg) of caffeine, according to nutritional information from the U.S. Department of Agriculture. By comparison, regular coffee averages 12-16 mg of caffeine per ounce.

So, yes, espresso technically has more caffeine, but in practice no one drinks just one ounce of coffee. You’re likely to have at least 8 ounces, which typically has 95 to 128 mg of caffeine.

However, caffeine counts for both espresso and coffee vary among brands and depend on the type of bean, the roast, the amount of coffee used, and the way it is prepared (brewed, French press, espresso machine, etc.) For example, at Starbucks, a shot of espresso has 75 mg of caffeine and an 8-ounce cup of its Pike Place medium roast coffee has 155 mg.

So why do some believe espresso delivers a bigger jolt than a regular cup of coffee?

Stephen Schulman, an independent coffee industry consultant in Charlotte, North Carolina, says it may have to do with how quickly you down each beverage. Espresso’s small serving size means you drink it faster than you would a cup of coffee, which is typically sipped more slowly.

Espresso can actually be a good option if you’re looking to cut down your caffeine intake, just so long as you keep it to one shot. You can either drink the espresso on its own, or if you’re looking for more of a lingering experience, order an espresso-based drink such as a cappuccino or a latte.