How Much Caffeine Per Day Is Safe?

When you look past the headlines, there's a surprising amount of agreement among food safety authorities. European bodies such as the European Food Safety Authority (EFSA), along with other national health authorities, have reviewed the evidence and landed on some simple reference points for healthy adults.

The headline figure is around 400 mg of caffeine per day. For most healthy adults, intakes up to roughly that amount are not associated with safety concerns. There's also a single-dose guide: about 200 mg in one sitting is considered fine, which is more relevant if you like a strong double shot rather than sipping slowly through the morning.

During pregnancy the reference point is lower – generally about 200 mg per day. These are general orientation values from authorities, not personal medical advice, and individual tolerance varies. But as a starting point, “up to about 400 mg a day” is the number most people can keep in mind.

A number in milligrams is hard to picture, so let's turn 400 mg into something you can actually hold. Caffeine content varies with beans, grind and brewing, but these are useful rough averages:

Filter coffee: around 90 mg per cup · Espresso: about 60–80 mg per shot · Matcha: roughly 35–70 mg per serving · Black tea: about 40–50 mg per cup · Cola: around 30–40 mg per glass.

In practice, 400 mg is a fairly generous amount: think roughly four cups of filter coffee, or a mix of a couple of coffees plus a tea and a matcha across the day. For a full breakdown of how different brews compare, see our guide on how much caffeine is in your coffee. And if you're weighing your morning coffee against a greener alternative, our matcha vs. coffee comparison breaks down the differences.

Whatever you pour, a good reusable coffee cup makes it easy to keep track of your cups – and to enjoy them slowly rather than on autopilot.

The 400 mg figure applies to healthy adults, but a few groups do best with less. During pregnancy and breastfeeding, the widely used reference point is around 200 mg per day, so it's worth being more mindful of hidden sources like tea, cola and chocolate.

Some people are simply more caffeine-sensitive than others – partly down to genetics and how quickly the body processes caffeine. If a single coffee leaves you jittery, anxious or with a racing heart, that's your body's signal to scale back, regardless of what any guideline says.

Teenagers and children also tolerate far less than adults, and authorities suggest much lower limits for younger age groups. As a gentle rule of thumb: the smaller the body and the more sensitive the person, the more it pays to keep caffeine modest.

Staying under 400 mg is only half the story – when you drink it matters just as much. Caffeine has a half-life of roughly 6 to 8 hours, which means that half of an afternoon coffee can still be circulating in your system at bedtime.

That's why a sensible cut-off time helps more than most people expect. A common rule of thumb is to stop caffeine about 6 to 8 hours before bed – so if you turn in around 10 pm, an early-afternoon coffee is usually the last of the day. If you're a sensitive sleeper, moving that cut-off even earlier can make a noticeable difference.

We go deeper into timing your last cup in our guide on coffee and sleep. The takeaway: it's less about giving up coffee and more about giving your body time to clear it before lights-out.