Understanding Grind Size

Written By Jason Wilger

One of the most overlooked variables in brewing great coffee is grind size. You can buy incredible beans, use filtered water, and follow a recipe perfectly — but if your grind size is off, your coffee will suffer.

Understanding grind size helps you control flavor, extraction, and consistency, whether you’re brewing at home or dialing in on a coffee cart.

What Is Grind Size?

Grind size refers to how coarse or fine coffee beans are ground before brewing. The grind determines how quickly water extracts flavors from the coffee.

  • Finer grinds slow water flow and extract more quickly

  • Coarser grinds allow water to pass through faster and extract more slowly

The goal is to find the grind size that matches your brewing method so extraction happens evenly.

Why Grind Size Matters

Grind size directly impacts extraction — how much flavor is pulled from the coffee grounds.

Under-Extraction (Too Coarse)

When the grind is too coarse:

  • Sour, thin, or hollow flavors

  • Weak body

  • Short brew time

Over-Extraction (Too Fine)

When the grind is too fine:

  • Bitter, harsh flavors

  • Dry, astringent finish

  • Sluggish or stalled brews

A well-matched grind size creates balance, sweetness, clarity, and body.

Grind Size by Brew Method

Different brew methods require different grind sizes due to contact time and filtration.

Extra Fine:

Best for: Turkish coffee

  • Powdery texture

  • Extremely high extraction

Fine:

Best for: Espresso

  • Similar to powdered sugar

  • Allows pressure to build for proper shot time

Medium-Fine:

Best for:

  • AeroPress (short brew)

  • Some pour-over recipes

Medium:

Best for:

  • Drip coffee makers

  • Flat-bottom pour-over brewers

Medium-Coarse:

Best for:

  • Cone pour-over (V60)

  • Chemex (depending on filter)

Coarse:

Best for:

  • French press

  • Cold brew

How to Adjust Grind Size Correctly

Instead of changing everything at once, adjust only the grind size first when dialing in.

Taste-Based Adjustments

  • Coffee tastes sour or weak → grind finer

  • Coffee tastes bitter or drying → grind coarser

Make small changes — even tiny adjustments can dramatically impact flavor.

Burr Grinders vs Blade Grinders

Grind consistency matters just as much as grind size.

Burr Grinders (Recommended)

  • Uniform particle size

  • Better flavor clarity

  • More control

Blade Grinders

  • Inconsistent grind

  • Uneven extraction

  • Harder to repeat results

A quality burr grinder is one of the best investments you can make for better coffee.

Final Thoughts: Grind Size Is Control

Grind size gives you control over how your coffee tastes. Once you understand how grind size affects extraction, brewing becomes more intuitive — and far more consistent.

If there’s one takeaway:

When coffee tastes off, adjust the grind first.

That single habit will improve your coffee more than almost any other change.

Jason Wilger
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Understanding Coffee Roast Levels