Grind Size Guide

Seven grind sizes, drawn to scale. Pick your brewer to see the size it needs, what it should look like, and how to tell when you've got it wrong.

Your brewer

Every dish is drawn at the same scale, about 9 mm across.

Under the loupe, 0.5–0.75 mm

Medium-fine

Pour-over lives on flow rate. This size lets water pass through a cone or flat bed at a steady pace, giving a clean, sweet cup in about three minutes.

Contact time
2:30–5 min

Dial it in by taste

Grinders differ, so treat the size as a starting point. Brew, taste, then move one step at a time.

Too fine

Bitter, harsh or drying. The water drains slowly or the shot runs long.

Grind coarser

Just right

Sweet and balanced, and the brew finishes close to its target time.

Keep the setting

Too coarse

Sour, thin or hollow. The water races through or the shot gushes.

Grind finer

Still not right? Diagnose your cup or read why coffee turns sour or bitter.

How it works

Grind size controls contact area and flow rate, so it is usually the fastest way to fix extraction. This guide helps you match particle size to each brew method.

  • Use a visual baseline before adjusting finer or coarser.
  • Reduce sour cups caused by overly coarse grinds.
  • Prevent bitterness and stalling caused by overly fine grinds.

  1. Filter by your brew method

    Each method needs a different particle size because immersion and percolation extract differently.

  2. Compare your current grind to the guide

    Use it as a reference point even if your grinder does not use the same number scale.

  3. Adjust based on taste and drawdown

    If coffee tastes sour or watery, go finer. If it tastes bitter or the brew runs too slowly, go coarser.

Questions

Why do grinder numbers not match between brands?

Manufacturers use different burr sets, zero points, and adjustment ranges, so the same number rarely represents the same particle size.

Should I change grind before changing ratio?

Usually yes. Grind size tends to have the biggest impact on extraction quality, while ratio changes strength more directly.

How do I know if my grind is too fine for pour over?

Common signs include a slow drawdown, muddy cup, bitterness, and stalled flow even when your pour technique is reasonable.

Does stale coffee affect how grind changes taste?

Yes. Older coffee can behave differently in the brewer, so grind adjustments may feel less predictable than they do with fresher beans.