How do I adjust the grind size for a V60?

The V60 is a pour-over method that relies on a paper filter and a conical shape to highlight the clarity and acidity of coffee. Because it is a manual brewing process, the grind size is the most powerful variable you have to control the extraction. A medium-fine grind is the standard starting point, but because every coffee bean has a different density and roast level, you will often need to dial in your grinder to achieve the best flavor.

When adjusting your grind, think about the relationship between surface area and water contact time. A finer grind increases the surface area, which slows down the water flow and increases extraction. If your coffee tastes bitter, dry, or astringent, it is likely over-extracted; you should adjust your grinder to a coarser setting to speed up the flow. Conversely, if your coffee tastes sour, thin, or lacks sweetness, it is likely under-extracted; you should adjust to a finer setting to increase the contact time.

It is important to make only one change at a time. If you change both the grind size and the water temperature, you won't know which adjustment improved the cup. Start by keeping your dose and water temperature constant, and adjust the grind in small, incremental steps. Most modern grinders have a 'stepped' or 'stepless' adjustment mechanism; get to know how yours behaves so you can make precise, repeatable changes.

In practice, the V60 is very sensitive to 'fines'—the tiny particles of coffee dust that can clog the paper filter and cause uneven extraction. If you find that your brew is stalling or tasting muddy, your grinder might be producing too many fines. While you cannot always control this, ensuring your burrs are clean and your beans are fresh can help. Ultimately, the goal is to find the 'sweet spot' where the acidity is bright, the body is balanced, and the finish is clean and lingering.