Brew time, extraction time, shot time — three words for the same principle. Yet, there’s confusion about when to actually start counting. At the press of a button? At the first drop? We'll clarify. (Looking for a complete guide to espresso preparation? You can find it in our Espresso Preparation Guide.)
Brew time is contact time
No matter if you call it brew time, extraction time, or shot time: it always refers to the contact time between water and coffee. Nothing more, nothing less.
Extraction begins the moment hot water hits your coffee puck. Not when the first drop falls into the cup. And it ends when the pump stops working and no more water is pushed through the coffee.
This sounds simple but regularly leads to misunderstandings in practice. Because between the moment you start the shot and the moment water actually reaches the coffee, one to four seconds can pass depending on the machine.
When to start counting?
The short answer: When your machine dispenses water.
With most machines, this happens almost immediately when you press the button or pull the lever. Then the button press is your starting signal. Some machines have a small delay of one or two seconds — you can easily test this by running it once without a portafilter and seeing when the water comes out. You then simply subtract this latency.
Why not count from the first drop? Because several seconds of extraction occur between water contact and the first drop in the cup. The water must first penetrate the entire coffee puck before anything comes out at the bottom. If you only count from the first drop, you're missing several seconds of contact time — and your recipe will be inaccurate.
And precisely the first few seconds of contact between water and coffee massively influence the entire extraction time. This is where it becomes clear whether the grind size has been chosen correctly or not.
What scales with drip detection can (and cannot) do
Some scales automatically start the timer as soon as the first drop falls onto the scale. This is not suitable for measuring brew time because it does not reflect the start of extraction.
Nevertheless, the function is not worthless. It can tell you something about your coffee: If the first drop appears after only three seconds, you've probably ground too coarsely. If nothing appears until after ten seconds, the grind size is probably too fine — or your puck has a problem. So, drip detection is useful as a diagnostic tool. Not as a stopwatch for brew time.
We've included our favorite scales in our shop. There's something for every price range.
Vibratory pump vs. rotary pump: The difference that changes your recipes
This is where it becomes practically relevant, as your pump determines how you need to interpret recipes.
A rotary pump builds pressure almost immediately. Within a few seconds, full brewing pressure is applied to the coffee. The brew chamber fills, water hits the puck, and it begins. With a rotary pump, pressing the button and the start of extraction are practically the same.
A vibratory pump works differently. It takes significantly longer to build pressure — the flow starts slowly and increases over several seconds. This means: The contact time is running, but the first phase is by no means as intense as with a rotary pump. The coffee is almost automatically gently pre-wetted before full pressure arrives.
This has consequences for your recipes.
The +3 second rule
Most recipes you get from roasters — "18 g in, 36 g out, 25 seconds" — are made with rotary pumps. This is because many roasters use professional commercial machines, and these almost always have rotary pumps.
If you have a vibratory pump at home (and this applies to the vast majority of home machines), you'll need about three more seconds for such recipes. So: 25 seconds stated in the recipe → around 28 seconds on your machine. This is not an exact law, but a good guideline to get into the right range.
At Kaffeemacher, we usually provide our recipes for both vibratory and rotary pumps and label them accordingly. If you're unsure with a roaster, ask which machine the recipe was created with. This gives you a better reference point than any rule of thumb.
Extraction time for single and double espresso
A question that often arises: Does a double espresso need to run longer than a single?
Not necessarily. If you use twice the amount of coffee in a larger basket for a double espresso and let twice the amount of water flow through, the contact time often remains similar. The resistance of the coffee puck and the flow rate scale proportionally. What changes is the brew ratio — and that should remain constant. A 1:2 ratio (18 g coffee → 36 g espresso) applies to a double just as a 1:2 ratio (9 g → 18 g) applies to a single. Although single espressos always have their own unique dynamics. A small amount of coffee powder does not offer resistance as evenly as the coffee powder in a double espresso. One reason why we recommend doing double extractions instead.
The extraction time is your control tool: If the time is not right with the same brew ratio, the grind size is probably incorrect.
Brew time as a guide, not a law
25 seconds is not a magic number. We provide recipes as a time window, not as a precise second-by-second instruction. The reason: every machine behaves slightly differently, every coffee reacts slightly differently, and two seconds more or less make little difference in taste for a well-tuned recipe.
Use brew time as a guideline. If you're at 18 g of coffee and 36 g of espresso and it takes 22 seconds, you're probably grinding a little too coarsely. At 35 seconds, too fine. But whether it's 26 or 28 seconds — try it and decide based on taste.
Ultimately, what's in the cup counts. Brew time helps you get there. But it doesn't replace your tongue.
Do you want to know how pre-brewing and pre-infusion influence extraction time? We explain this in the article Pre-brewing in espresso: What does it really do? — including the question of why 3 seconds of pre-infusion is almost always too short.
This article is also available as a video on our YouTube channel.
