How much caffeine is in a cup of cold brew?

Cold brew is often surrounded by myths regarding its caffeine content. Because the process involves steeping coarse grounds in cold water for 12 to 24 hours, many assume the long contact time extracts significantly more caffeine than hot brewing. While the long duration does allow for substantial extraction, research suggests that caffeine extraction actually plateaus after a few hours, meaning the 'extra' time doesn't necessarily keep pulling more caffeine out of the grounds.

The real driver of caffeine in cold brew is the ratio of coffee to water. Cold brew is almost always made as a concentrate, using significantly more dry coffee per ounce of water than a standard drip brew. When you dilute that concentrate to a drinkable strength, you are often left with a beverage that is more caffeine-dense than a typical cup of hot coffee. A 12-ounce serving of cold brew can easily contain 150 to 200 milligrams of caffeine, depending on how strong the concentrate was brewed.

It is important to note that 'cold brew' is not a standardized product. A coffee shop might serve a cold brew that is diluted 1:1, while another might serve it straight from the concentrate. This variability makes it difficult to provide a single, universal number for caffeine content. If you are sensitive to caffeine, it is safer to treat cold brew as a high-caffeine beverage and adjust your consumption accordingly.

In practice, the brewing method is less of a factor than the concentration. If you are brewing at home, you can control the caffeine level by adjusting your coffee-to-water ratio. If you find the caffeine hit too strong, simply dilute your concentrate with more water or ice. Understanding that cold brew is a concentrated extraction allows you to enjoy it as a refreshing, high-caffeine option while keeping your daily intake in check.