Tamping means pressing the coffee grounds down evenly in the portafilter so the water doesn't shoot through loose pockets. Keep the tamper level, apply 10–15 kg of pressure. Consistency is much more important than sheer force.

What does tamping mean and how do you do it right?

Tamping means pressing the coffee grounds down evenly in the portafilter so the water doesn’t shoot through loose pockets. Keep the tamper level, apply 10–15 kg of pressure. Consistency is much more important than sheer force.

Why that is

Before the espresso machine unleashes 9 bars of pressure onto the coffee puck, the grounds in the portafilter must be compact and evenly distributed. Loosely poured coffee has air pockets and voids. Water seeks the path of least resistance — it will blast right through those loose spots (channeling) and bypass the denser areas completely. The result: an uneven extraction, yielding a watery yet bitter espresso.

Tamping compresses the coffee into a uniformly dense layer. This forces the water to meet a consistent barrier of resistance, soaking the entire puck evenly.

The technique:

1. Distribute the coffee evenly in the basket — before you tamp, distribution is actually more critical than the pressing itself. A finger-tap, a leveler, or a WDT tool (needle distributor) helps immensely.
2. Place the tamper squarely on top of the grounds. The tamper diameter should snugly fit the basket (58 mm is the standard for most commercial portafilters).
3. Press straight down with even pressure. The force should come from your wrist and upper arm, not just your fingers.
4. Do not twist — a light polish (a gentle spin without pressure) is optional and highly debated. What matters most is that the tamper remains perfectly level.

How much pressure? 10–15 kg is plenty. Years ago, 15–20 kg was often recommended, but modern consensus shows: once the coffee is fully compressed, adding more pressure offers zero benefit. What’s crucial is that the pressure is the same every time, and the tamper is completely dead-level.

A crooked tamp is far worse than a light one. If one side of the puck is denser than the other, the water will preferentially flow through the thinner side — classic channeling.

For ironclad consistency, you can use calibrated tampers (like Normcore), which click or yield at a predefined pressure. This eliminates the guesswork and ensures every single puck is compressed exactly the same way.

In practice at Green Wall Coffee

At Sophienstraße 27, we use a calibrated tamper — every barista tamps with the exact same pressure. The biggest tip I give beginners: worry less about the pressure, and more about your distribution. An evenly distributed, lightly tamped puck makes significantly better espresso than an unevenly distributed puck pressed with all your might.

Related questions

• How much pressure do I need when tamping?
• What is channeling and how do I prevent it?
• How do I make the perfect espresso?

You can find more in-depth information in the article How to make perfect espresso. Or drop by Sophienstraße 27 — Mon–Fri 8am–5pm, Sat 10am–5pm.