The Coffee Grind Size Chart You Should Be Using

It’s Tuesday morning. You’ve just spent $24 on a bag of single-origin beans that promise notes of “jasmine, blueberry, and whispered secrets.” You brew it. You take a sip. And suddenly, your mouth implodes. It tastes like battery acid mixed with a handful of sawdust.

Is the bean a lie? Probably not. The culprit is almost certainly the way you smashed those beans into oblivion. Welcome to the chemistry of coffee, where the difference between a life-changing cup and sink-water often comes down to a few hundred microns.

Most guides will tell you to set your grinder to “medium” and hope for the best. That’s not how we do things here. If we’re going to treat caffeine like the essential fuel it is, we need to treat coffee brewing like the science experiment it is. This is your guide to understanding particle distribution, extraction yield, and why the coffee grind size chart is the most important tool in your kitchen.

The Science of Coffee Grind Size: Why It Matters

Before we dive into the data, let’s kill a myth: there is no single “best grind size” for all coffee. A coffee grind size that works perfectly for a French Press will absolutely ruin an espresso shot. It all comes down to surface area and contact time.

Think of coffee brewing as dissolving a solid into a liquid. When you grind coffee, you are breaking a large bean into thousands of smaller pieces to increase the surface area. The more surface area exposed to water, the faster the water can extract flavor compounds (oils, acids, and sugars). This is the fundamental rule of the brew method hierarchy.

If your coffee particles are large (coarse), water needs more time to penetrate them and pull out the good stuff. If the particles are microscopic (fine), the water extracts flavor instantly. The goal is to match the size of your coffee grounds to the amount of time the water spends in contact with them.

If you get this wrong, you get bad coffee. Too coarse, and the water rushes past without grabbing enough flavor, leading to a sour, salty, under-extracted cup. Too fine, and the water gets stuck, pulling out bitter tannins and dry distinct flavors, resulting in an over-extracted mess. The correct grind is the one that balances this equation perfectly.

The Ultimate Coffee Grind Size Chart (Visuals & Data)

Numbers on a grinder dial are arbitrary. A “10” on my grinder might be a “4” on yours. To actually standardize this, we use microns (μm). One micron is one-millionth of a meter. For context, a grain of table salt is about 500 microns. If you really want to geek out, you can use a tool like the Kruve Brewler to measure your grounds against a reference scale, but for most of us, visual comparisons to common kitchen ingredients work best.

Here is the breakdown of the ultimate coffee grind size spectrum.

Coarse Grind Size: Best for Cold Brew Coffee and French Press

Let’s start at the chunky end of the spectrum. A coarse grind size is essential for immersion brewing methods. In these methods, the water sits with the coffee for a long time—anywhere from 4 minutes for a French Press to 24 hours for cold brew.

Because the contact time is so long, you need to slow down the extraction. If you used a fine powder for cold brew coffee, you’d end up with a sludge that tastes like aspirin. You want chunks that look like sea salt. This allows the water to slowly seep into the core of the bean over hours, extracting the sweet, chocolatey low notes without the acidity.

For French press coffee, the logic is similar but faster. You need the particles large enough to be caught by the metal mesh filter. If you grind too fine, you’ll end up with a muddy cup full of sediment—a phenomenon coffee nerds politely call “high turbidity” and normal people call “grit in my teeth.”

Medium Grind: The Go-To for Drip Coffee Makers

This is the workhorse setting. If you have a standard automatic machine, a medium grind size is your baseline. Think of the texture of regular sand you’d find at a playground. This size is designed for drip coffee makers using flat-bottomed filters.

In a drip machine, gravity pulls water through the bed of coffee. The grind needs to provide just enough resistance to hold the water back for a few minutes, but not so much that the basket overflows. If your morning pot tastes bitter, your medium grind might be drifting too fine. If it tastes watery and weak, you’re likely too coarse, and the water is channeling straight through without saying hello to the flavor compounds.

For many coffee lovers, the medium setting is where they live. It’s safe, it’s consistent, and it works for brewing large batches.

Pour-Over Coffee and the Nuance of Medium-Fine Grind

Here is where we start entering specialty territory. Pour-over coffee methods like the Hario V60, Kalita Wave, or Chemex generally require a medium-fine grind. This is slightly finer than sand, closer to table salt.

Why go finer? Because pour-over cones usually use paper filters that are thicker than standard drip filters, and the shape of the cone (especially the V60) encourages faster flow. To compensate for gravity trying to rush the water through, you tighten up the grind. This increases the surface area and slows the flow rate physically, ensuring the water through the coffee bed captures the floral and acidic notes these brewers are famous for.

However, this is also the most volatile range. A slight shift in particle size here can drastically change the draw-down time. If your V60 is taking 4 minutes to drain instead of 3, you’ve ground too fine. If it drains in 2 minutes, you’re too coarse. It requires you to fine-tune your grind frequently.

Grind for Espresso: Pressure, Resistance, and the Fine Grind

Espresso requires a fine grind. There is no negotiating this. We are no longer relying on gravity; we are using a pump to force water through a puck of coffee at 9 bars of pressure (about 130 PSI). If you used a medium grind, that high-pressure water would fly through the puck in 5 seconds, giving you salty brown water.

The grind for espresso needs to be fine enough to create a solid barrier against that pressure. The resistance created by the packed coffee grounds is what creates the crema and the rich, syrupy body. The texture should feel like granulated sugar or fine beach sand.

This is also where your equipment matters most. A standard blade grinder cannot produce a consistent grind for espresso. It produces “boulders” and “fines.” The boulders let water channel through instantly, while the fines clog the basket. To get this right, you need a dedicated burr grinder capable of micro-adjustments.

Grind Size for Turkish Coffee: As Fine as It Gets

If you keep turning the dial past espresso, you reach the grind size for Turkish coffee. This is an extra-fine grind, essentially a powder that feels like flour or cocoa. In this method, the coffee is boiled directly in the water and is not filtered out. You drink the suspension.

Because the grounds are never removed, they must be so fine that they eventually sink to the bottom of the cup and form a mud-like layer. If the grind is even slightly too coarse, the particles will float, and you’ll be chewing your coffee instead of drinking it.

The Best Grind Size is Consistent: Why You Need a Burr Grinder

We can look at the coffee grind size chart all day, but it’s useless if your tools can’t execute it. This brings us to the most critical piece of advice in this entire guide: throw away your blade grinder.

Blade grinders don’t grind; they chop. They spin a metal blade at high speed, shattering beans randomly. The result is a mix of massive chunks (boulders) and microscopic dust (fines). When you brew this mixture, the fines over-extract (bitter) and the boulders under-extract (sour). You get a cup that is somehow bitter and sour at the same time. It’s a culinary disaster.

To achieve a consistent grind, you need a burr grinder. Burr grinders use two abrasive surfaces to crush the beans to a uniform size. The distance between the burrs determines the size, ensuring every particle is roughly the same.

For most home brewers, the Baratza Encore is the gold standard. It’s built like a tank, has 40 distinct settings, and allows you to dial in everything from French Press to a decent espresso. If you are serious about coffee brewing methods, this is the single most impactful upgrade you can make—more important than the machine, the kettle, or even the beans.

Troubleshooting: How to Adjust the Grind Based on Taste

Even with a chart, you will eventually need to trust your palate. Beans age, humidity changes, and different roasts shatter differently. You will need to adjust the grind based on what you taste. Here is the simple heuristic:

If the coffee tastes SOUR, SALTY, or ACIDIC:

This is under-extraction. The water moved too fast or couldn’t get inside the particles. You need to extract more.
The Fix: Use a finer grind size.

If the coffee tastes BITTER, DRY, or HOLLOW:

This is over-extraction. The water stripped everything good and then started pulling out plant fibers and tannins. You need to extract less.
The Fix: Use a coarser grind size.

If the brew time is too fast or slow:

Physical indicators matter too. If your pour-over is stalling and creating a pool of water that won’t drain, your grind size allows too little flow. You have clogged the filter with fines. Go coarser. Conversely, if your espresso shot pulls in 10 seconds, tighten it up.

Matching Grind Size to Different Brew Methods

We’ve covered the majors, but the world of speciality coffee is vast. Here is a quick reference for matching different grind sizes to specific brewers:

• AeroPress: This is the chameleon. You can use a medium grind with a long steep time (2-3 minutes) or a fine grind with a short steep time (1 minute). It’s versatile.
• Siphon: Requires a medium grind, slightly finer than drip but coarser than V60.
• Moka Pot: Often confused with espresso. It needs a fine grind, but not espresso fine. Think somewhere between table salt and sugar. Too fine, and the pressure valve might explode (fun to watch, hard to clean).
• Chemex: Because the filters are bonded and thick, use a medium-coarse grind. If you use a V60 setting on a Chemex, it will choke.

Final Thoughts: The Pursuit of the Perfect Cup

Mastering the coffee grind size chart isn’t about being a snob; it’s about getting what you paid for. You are buying beans that have been farmed, harvested, processed, roasted, and shipped with incredible care. Grinding them incorrectly is like buying a Ferrari and putting diesel in it.

Start with the recommended settings, but don’t be afraid to experiment. Use your tongue as the final judge. If you can control your grind setting, you can control your morning. And frankly, on a Tuesday morning, a little bit of control is all we’re really looking for.

Frequently Asked Questions

Can I grind my coffee beans in a blender?

Technically, yes, but you shouldn’t. A blender acts exactly like a blade grinder, shattering beans into inconsistent chunks. You will generate heat that degrades the oils, and the uneven coffee particle size will lead to uneven extraction. If you don’t have a burr grinder, you are often better off buying pre-ground coffee from a local roaster who can grind it fresh for your specific brew method.

Why is grind size consistency so important?

Consistency ensures that all particles extract at the same rate. If you have a mix of dust and boulders, the dust extracts instantly (bitter) while the boulders barely extract at all (sour). A consistent grind allows you to target the “sweet spot” of extraction where the coffee tastes balanced, sweet, and complex.

Have you brewed a cup of coffee that tastes sour?

A sour taste is the hallmark of an incorrect grind size—specifically, one that is too coarse. The water passed through the coffee bed too quickly to dissolve the sugars and balancing compounds. To fix a sour cup, adjust your grinder to a finer setting to increase the contact time and surface area.

Does roast level affect how I should grind?

Yes. Darker roasts are more brittle and dissolve easier than light roasts. Generally, you might want a slightly coarser grind for dark roasts to prevent bitterness, and a slightly finer grind for light roasts to help extract those stubborn, dense flavors. You have to fine-tune your grind as you switch beans.

How often should I clean my coffee grinder?

Old coffee oils go rancid and will ruin the taste of your coffee regardless of your grind size. You should do a quick brush out of your burrs once a week and a deep clean every month or two. Keeping the burrs clean also helps maintain the grind particle size consistency.

What is the difference between “fine” and “medium-fine”?

It sounds like splitting hairs, but in brewing, it’s huge. “Fine” packs together tightly, creating resistance (espresso). “Medium-fine” allows for gravity drainage (pour-over). If you swap them, you either choke your brewer or make a watery mess. Using a grind size guide helps visualize this, but small adjustments on your dial make a massive difference in flow rate.