An average 240ml (8oz) cup of brewed coffee contains around 80-100mg of caffeine. A single espresso shot contains roughly 60-65mg, while a double espresso (doppio) contains about 120-130mg. Exact caffeine levels vary depending on bean type, brew method and serving size. All figures here are based on typical brew strength rather than unusually strong or weak recipes.
Caffeine Content by Coffee Type
Caffeine isn’t a fixed number. It changes based on dose and serving size. Below are reliable everyday ranges for common coffee types, with the main reasons they swing up or down.
Brewed Coffee (Filter / Drip)
A typical 240ml (8oz) brewed coffee usually lands around 80-100mg of caffeine. It varies because some people brew stronger (more coffee per litre), some brew weaker, and cup sizes change the total caffeine more than most realise. In cafés, “one coffee” can be 300-450ml, which is why commercial servings can feel noticeably stronger even when the coffee doesn’t taste intense.
Espresso (Single & Double)
A single espresso (30ml) typically contains 60-65mg of caffeine. A double espresso (doppio) is usually 120-130mg. Espresso is stronger per ml, but because the serving is small, it isn’t always higher per drink than a full cup of filter coffee.
Here’s why people get confused: many speciality cafés pull espresso using a double basket as standard. That’s how we pull it in our own roastery. So what’s listed as “espresso” on the menu may already be a double shot in practice, which is why “espresso caffeine” numbers can look inconsistent online.
If you want the simple version of servings and what cafés usually pull, jump to how much caffeine is in a shot of espresso.
Full breakdown: doppio vs espresso.
Instant Coffee
Instant coffee typically sits around 30-90mg per 240ml. It’s often lower because people use less coffee per cup, and the final strength depends on how many teaspoons you add. One sachet in a big mug will be much lower than a heaped spoon in a small cup.
Decaf Coffee
Decaf coffee is not completely caffeine-free. Most decaf contains around 2-5mg of caffeine per 240ml cup, although the exact amount depends on the bean and the decaffeination process used. Compared to regular coffee, the caffeine level is minimal, but it isn’t zero. If you’re sensitive to caffeine or avoiding it later in the day, decaf remains the lowest-caffeine option available. For a detailed breakdown, see our guide on how much caffeine is in decaf coffee.
Cold Brew Coffee
Cold brew is the one people misjudge most, especially when they’re drinking concentrate that hasn’t been properly diluted. A served cold brew can land anywhere from 100-200mg per 240ml depending on how strong the concentrate is and how much it’s diluted with water or milk. Commercial cold brew served undiluted can exceed this.
Because cold brew is often diluted differently in cafés and at home, its caffeine content is less predictable than espresso or filter coffee. For a full breakdown of ratios and strength, see our guide to cold brew coffee.
Why Caffeine Levels Vary
Caffeine isn’t fixed. Two cups that look similar can contain very different amounts. The difference comes down to bean type, roast level and extraction method.
Bean type is the biggest driver. Robusta naturally contains significantly more caffeine than Arabica. According to research published in the Journal of Agricultural and Food Chemistry, Robusta species consistently show almost double the caffeine concentration. If you want a deeper breakdown of flavour and structure differences, see our guide to Arabica vs Robusta.
Roast level makes a small difference by weight. Lighter roasts retain slightly more caffeine per gram because they lose less mass during roasting. The difference isn’t dramatic, but when measured by weight rather than scoop size, lighter roasts can contain marginally more caffeine.
Grind size affects how efficiently caffeine is extracted. A finer grind exposes more surface area, allowing water to extract compounds more quickly. We explain this in more detail in our guide on how to grind coffee beans properly.
Brew ratio and contact time change total yield. The more water that passes through the coffee, and the longer it stays in contact, the more caffeine ends up in the cup. Extending an espresso shot or steeping a cafetière longer will usually increase caffeine slightly. For practical examples, see our guides on dialling in espresso and brewing with a cafetière.
Serving size is often the biggest factor. A large mug of filter coffee can easily contain more caffeine than a small espresso simply because you’re drinking more liquid. Always compare total milligrams per serving, not just concentration per millilitre.
How Much Caffeine Is in a Shot of Espresso?
A single espresso shot (around 30ml) typically contains 60-65mg of caffeine. A double espresso (doppio) is usually 120-130mg, depending on dose and the coffee used.
Many speciality cafés pull espresso using a double basket as standard. So what’s listed as “espresso” on the menu may already be a double shot in practice.
If you want the terminology made simple, see our guide on what a doppio coffee is.
How Much Caffeine Is Safe Per Day?
For most healthy adults, up to 400mg of caffeine per day is considered safe. The U.S. Food and Drug Administration (FDA) states that 400mg per day is not generally associated with harmful effects in healthy adults.
To put 400mg into context, that’s roughly four to five standard 240ml cups of brewed coffee, or three large takeaway coffees depending on size. With espresso based drinks, it could be three double-shot drinks in a day.
The European Food Safety Authority (EFSA) provides similar guidance, noting that up to 200mg in a single dose and up to 400mg per day from all sources does not raise safety concerns for the general adult population.
For pregnant or breastfeeding women, recommendations are lower. EFSA advises limiting caffeine intake to around 200mg per day during pregnancy.
Individual sensitivity varies. Some people feel jittery at 150mg, while others tolerate more without noticeable effects. If you experience restlessness, anxiety, poor sleep or rapid heartbeat, your personal limit may be lower than the general guidance.
Caffeine Comparison Table
These are average ranges for standard strength drinks.
| Drink | Typical Serving | Typical Caffeine (mg) |
|---|---|---|
| Brewed coffee | 240ml | 80–100 |
| Espresso | 30ml | 60–65 |
| Double espresso | 60ml | 120–130 |
| Instant | 240ml | 30–90 |
| Decaf | 240ml | 2–5 |
| Cold brew | 240ml | 100–200 |
Why Coffee Strength Feels Different to Caffeine
One thing we see regularly is people confusing taste intensity with caffeine content. A dark roast can taste bold but contain similar caffeine to a lighter roast. A milky drink can taste smooth but still carry the caffeine of a double espresso underneath. Strength of flavour and caffeine level are not the same thing.
If you want to compare drinks properly, look at total milligrams per serving rather than how strong it tastes.
How Much Caffeine Is in Coffee in the UK?
In the UK, caffeine levels are broadly similar to US figures, but serving sizes vary more than people expect. A standard home-brewed cup is often treated as around 240ml, which usually lands around 80-100mg depending on strength.
Espresso is typically served as a 30ml shot, but café recipes vary. If you’re comparing drinks, the most useful thing to check is whether the café is serving a single or double shot. (We explain that properly above.)
High-street chains often serve larger drinks overall, which increases total caffeine even when the coffee doesn’t taste “stronger”. In the UK, the biggest swing is usually portion size, not the bean.
FAQs
How much caffeine is in a cup of normal coffee?
A standard 240ml cup of brewed coffee typically contains 80-100mg of caffeine. The exact amount depends on how strong it’s brewed, the type of bean used, and the serving size. Larger mugs or stronger brew ratios can push that higher. In cafés, takeaway cups are often bigger than 240ml, which increases the total caffeine even if the coffee doesn’t taste particularly strong.
Is 200mg of caffeine a lot?
For most healthy adults, 200mg is a moderate amount. It’s roughly equivalent to two standard cups of brewed coffee or a strong double espresso plus a filter coffee. The FDA considers up to 400mg per day safe for most adults. Some people feel alert at 100mg, while others tolerate much more without noticeable effects.
How much caffeine is in a double espresso?
A double espresso (doppio) typically contains 120-130mg of caffeine. This assumes around 18-20g of coffee extracted to a 1:2 ratio. In many modern speciality cafés, a double is the default espresso recipe, which is why caffeine numbers for “espresso” can appear inconsistent online. Always check whether the serving refers to a single or double shot.
How much caffeine is in coffee per 100ml?
Per 100ml, brewed filter coffee usually contains around 30-45mg of caffeine, depending on strength. Espresso is far more concentrated, often around 200mg per 100ml, but it’s rarely consumed in that volume. Cold brew can vary widely depending on dilution. Per 100ml figures are useful for comparison, but total serving size matters more in practice.
Is espresso stronger than coffee?
Espresso is stronger per millilitre, but not necessarily stronger per drink. A single espresso contains roughly 60-65mg of caffeine in 30ml, while a full 240ml cup of filter coffee may contain 80-100mg. Espresso tastes more intense because it’s concentrated, but a larger brewed coffee can contain more total caffeine overall.
Does darker roast have more caffeine?
Not necessarily. Caffeine content is fairly stable during roasting. By weight, lighter roasts can contain slightly more caffeine because they’re denser. By scoop volume, darker roasts may appear similar or slightly higher because they expand and become less dense. In practical brewing terms, roast level changes flavour far more than caffeine content.