Coffee Grind Size Chart
Interactive grind size reference for every brew method. Filter by coarseness, see micron ranges and visual size comparisons, and understand how grind affects extraction and brew time.
Grind Size Chart
| Brew Method | Grind Size | Particle Size | Ratio | Brew Time |
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How Grind Size Affects Coffee Extraction
Grind size determines the surface area of coffee exposed to water. A finer grind exposes more surface area, which accelerates extraction — water contacts more of the coffee's soluble compounds per unit of time. This is why espresso, which brews in 25–30 seconds, requires a very fine grind, while cold brew, which steeps for 12–24 hours, needs an extra coarse grind to prevent over-extraction during its long contact time.
The key relationship is between grind size and brew time: finer grinds combined with long brew times lead to over-extraction and bitterness. Coarser grinds with short brew times lead to under-extraction and sourness. The correct grind for any method is the one that achieves the target flavour balance within the method's prescribed brew time. Grind size is how you control brew time — if your pour over drains in 2 minutes, grind finer; if it takes 5 minutes, grind coarser.
Grind consistency matters as much as average grind size. Blade grinders produce inconsistent particles — a mix of very fine powder and large chunks — which causes uneven extraction. Burr grinders produce a uniform particle size, allowing predictable, consistent extraction. For any method where you're trying to dial in a specific coffee to water ratio, grind consistency is essential to getting repeatable results.
Pro Tips for Getting Grind Size Right
- Use a burr grinder, not a blade grinder. Blade grinders chop coffee unevenly, producing a mix of fine powder and large chunks. This causes simultaneous over and under-extraction in the same brew. Burr grinders — even affordable flat or conical burr models — produce consistent particle sizes that allow predictable, repeatable extraction.
- Adjust grind size based on brew time, not taste alone. If your pour over finishes in 2 minutes but tastes fine today, it will taste sour tomorrow when your calibration drifts. Use brew time as your primary feedback: adjust until the brew hits the target window, then fine-tune within that window based on taste.
- Grind fresh, every time. Ground coffee stales within 15–30 minutes at room temperature due to rapid off-gassing and oxidation. Pre-ground coffee loses the volatile aromatic compounds that define a coffee's character. Grinding immediately before brewing is one of the highest-impact improvements available, regardless of how expensive or fresh your beans are.
- Dial in grind before changing ratio. New bag of coffee? Change grind size first, keep ratio constant. Different grind sizes reach optimal extraction at different ratios, so fix one variable before adjusting the other. Once your brew time is back in range, taste and then adjust ratio if needed.
- Finer doesn't always mean stronger. A grind that's too fine for your brew method extracts bitter compounds excessively, making the coffee taste harsh and unpleasant rather than strong. True strength comes from adjusting the coffee to water ratio, not grinding finer. Match grind to method first, then adjust the ratio for strength.
Frequently Asked Questions
Medium grind is standard for automatic drip coffee makers — particles about the texture of regular beach sand. This produces a brew time of 4–6 minutes in most machines, which aligns with the SCA's recommended extraction window. If your drip coffee is consistently bitter, try a slightly coarser grind; if it's weak and sour, grind slightly finer.
AeroPress is versatile and works across a wide grind range — medium-fine (like table salt) for the standard 1–2 minute method, fine for the inverted method with longer steeps. AeroPress is the most forgiving brewing device for grind size experimentation. Start at medium-fine and adjust based on your preferred steep time and flavour target.
Espresso operates at 9 bars of pressure with a 25–35 second extraction window. At this pressure, even tiny differences in grind size (a fraction of a turn on a quality grinder) significantly change flow rate and extraction. A grind that's too coarse causes the shot to run fast and under-extract — thin, sour, pale crema. Too fine and the shot chokes, over-extracts — dark, bitter, harsh. This narrow tolerance is why espresso grinders are significantly more expensive than filter grinders.
Yes. Dark roasts are more porous and extract faster than light roasts — they may need a slightly coarser grind to achieve the same brew time. Light roasts are denser and more resistant to extraction, sometimes requiring a finer grind. This is especially noticeable in espresso, where switching from a medium to a light roast typically requires grinding finer and may also need a longer yield ratio to fully develop the coffee's flavour.