Coffee Grind Size Calculator

☕ The Ultimate Coffee Grind Calculator

Dial in the perfect cup by balancing method, roast, and strength.

Recommended Setting

Medium
FINE
(Espresso)
MEDIUM
(Drip)
COARSE
(French Press)

Texture Target:

Micron Range:

Why “Close Enough” Isn’t Good Enough

Grind size isn’t just about fitting the coffee into the machine; it controls the Surface Area available to the water. This directly dictates how fast flavors are extracted.

Coarse Grind
Less surface area exposed.
Water penetrates slowly.
Best for long brew times (French Press).

Fine Grind
Massive surface area exposed.
Water extracts flavor instantly.
Best for pressure/speed (Espresso).

Visual Reference Table

Use this table to visualize the texture if you don’t have a micron-specific tool.

Grind Name Microns (μm) Texture Comparison Used For
Extra Fine 200 – 400 Powdered Sugar / Flour Turkish Coffee, Espresso
Fine 400 – 600 Table Salt Moka Pot, AeroPress
Medium 600 – 900 Regular Sand / Sea Salt V60, Auto-Drip, Siphon
Coarse 900 – 1100 Kosher Salt Chemex, Clever Dripper
Extra Coarse 1100+ Rock Salt / Peppercorns French Press, Cold Brew

Step-by-Step: Dialing It In

Using the tool above is just the starting point. Here is the professional 5-step workflow to getting the perfect grind.

1. Establish the Baseline

Input your method into the calculator above. This gives you your “Safe Zone.” For example, if it says “Medium,” set your grinder to the middle setting.

2. The Tactile Check

Grind a small amount (1 gram). Rub it between your fingers. Does it match the description (e.g., does it feel like salt or like flour)? If it feels too coarse compared to the description, adjust finer immediately.

3. The First Brew (The Standard)

Brew your coffee using your standard ratio (usually 1:16, or 60g coffee per 1L water). Pay attention to the Total Brew Time.
Example: A V60 should take about 3:00 minutes. If it drains in 2:00, your grind is too coarse. If it takes 4:30, it is too fine.

4. The Taste Diagnosis

Taste the coffee when it cools slightly. This is the manual calculation part:

  • Is it Sour, Salty, or Thin? This is UNDER-extraction. The chunks were too big. Solution: Grind Finer.
  • Is it Bitter, Dry, or Astringent? This is OVER-extraction. The dust was too fine. Solution: Grind Coarser.

5. The Micro-Adjustment

Only change one variable at a time. Do not change your water temperature or dose. Just move your grinder one “click” in the direction of the solution found in Step 4.

Comprehensive FAQ

Can I manually calculate grind size without tools?
Not mathematically, but sensually. The “Manual Calculation” is done by timing your brew.

The Rule of Thumb: If your Pour Over finishes 30 seconds faster than the recipe calls for, you must calculate that your grind allows water to flow too fast. Manually adjust your grinder 2 steps finer to increase flow resistance.
Why do Light and Dark roasts need different sizes?
Density vs. Solubility.
Light roasts are hard and dense. Water has a hard time getting flavor out of them, so we grind Finer to help the water out.
Dark roasts have been cooked longer; they are brittle and dissolve very easily. If you grind them too fine, the water extracts too much bitter ash flavor. We grind Coarser to hold back the extraction.
Blade Grinder vs. Burr Grinder: Does it really matter?
Yes, critically. A Blade Grinder (like a blender) shatters beans randomly. You get both dust (bitter) and boulders (sour) in the same cup. You cannot “dial in” a blade grinder.

A Burr Grinder acts like a pepper mill, crushing beans to a uniform size. This tool and these charts are only accurate if you are using a burr grinder.
My grinder settings are just numbers (1-40). How do I translate this?
Every grinder manufacturer is different. A “10” on a Baratza is different from a “10” on a Breville.

How to calibrate: Use the “Texture Comparison” in the tool above. Find the setting on your grinder that produces “Table Salt” texture. Mark that as your “Medium-Fine” baseline and adjust up or down from there.
What is “Fines Migration” / Why does my brew stall?
Even on good settings, coffee produces microscopic dust called “fines.” If you grind too fine, or your grinder is low quality, these fines sink to the bottom of your filter and clog the paper, stopping the water flow.

Fix: Grind slightly coarser, or pour the water more gently to avoid agitating the bed.
Does grind size affect caffeine content?
Indirectly, yes. Caffeine is very water-soluble. A finer grind exposes more surface area, allowing caffeine to be released faster. However, brewing time and coffee-to-water ratio are bigger factors in total caffeine kick than grind size alone.