How do I grind coffee correctly?

Grind size controls how fast water extracts from coffee. Longer contact time needs coarser grounds; shorter contact needs finer. But the more important variable is consistency: uniform particles extract evenly, and a mix of dust and chunks tastes simultaneously bitter and sour.

What you'll need

• Burr grinder
• Coffee beans
• Scales (optional)

Step by step

1. Match the grind to the brewing method's contact time.Espresso (25–30 seconds): fine, like table salt or finer. Pour-over (3 minutes): medium, like sand. Cafetière (4–9 minutes): coarse, like sea salt. Cold brew (12 hours): coarser still.
2. Use a burr grinder rather than a blade grinder.Burrs crush beans to a set size; blades chop randomly, producing dust and boulders. This is the single biggest quality difference available.
3. Grind immediately before brewing.Ground coffee loses most of its aromatics within about fifteen minutes. Nothing about storage changes that.
4. Grind only what you need.Weigh the beans rather than grinding a batch. 60g per litre of water is the standard starting ratio.
5. Adjust grind by one step at a time and taste.Finer if the coffee is sour; coarser if bitter. One step, taste, repeat.
6. Watch the brew time as a diagnostic.A pour-over much faster than 3 minutes means the grind is too coarse; much slower means too fine.
7. Clean the grinder regularly.Old oils in a grinder go rancid and taint every subsequent grind. Brush it out weekly.
8. Expect to adjust grind when you change beans.Different roasts and different ages of bean grind differently. The dial setting is not transferable.

Tips

• If you can only upgrade one thing, upgrade the grinder rather than the brewer. Grind consistency affects the cup more than the machine does.
• Hand grinders with steel burrs are excellent value and outperform cheap electric blade grinders comfortably.
• Coffee grinds differently as it ages and dries out, so a setting that worked last week may need adjusting.

Common mistakes

• Using a blade grinder — It produces dust and boulders. The dust over-extracts and the boulders under-extract, so the cup is bitter and sour at once.
• Grinding in advance — Ground coffee stales within minutes to hours. It is the largest avoidable quality loss.
• Changing grind and dose at the same time — You cannot tell which change produced the result.

Questions people ask