What grind size should I use for each brewing method?

Espresso wants a fine grind of roughly 200 to 400 microns, about the look of table salt. Moka pot sits just coarser than that. Pour over and filter want a medium grind of roughly 500 to 800 microns, like coarse sand or granulated sugar. French press wants a coarse grind of roughly 800 to 1,000 microns, closer to coarse sea salt. Cold brew wants coarse as well, though published charts disagree on how coarse, ranging from 700 up to 1,500 microns depending on who you ask. An AeroPress works across almost the whole range. Treat the numbers as landmarks: no home grinder shows microns, and the right setting for your beans sits in a range rather than on a point.

How do I know if my coffee is ground too fine or too coarse?

Taste it, then time it. A sour, sharp or thin cup means the water did not extract enough, so grind finer. A bitter, dry or hollow cup means it extracted too much, so grind coarser. Timing gives you an answer before you taste: a double espresso should take about 25 to 30 seconds to pour, and a single cup pour over should finish draining in three to four minutes. A shot that runs in 15 seconds is too coarse, and a pour over that stalls past six minutes is too fine. Change the grinder by one or two steps at a time and brew again rather than making a large jump.

Why does my coffee taste bitter and sour at the same time?

Because the grind is uneven rather than the wrong size, so you are drinking over-extracted and under-extracted coffee from the same brew. The dust in an uneven grind has a large surface area for its volume, so water strips it fast and pulls out the bitter compounds that normally come out last. The larger pieces never give up what is inside them and contribute sharp, sour flavours. Going finer or coarser will not fix it, because the two problems move in opposite directions. This is the standard signature of a blade grinder, which chops rather than sizing particles. A burr grinder is the fix.

Can I use a filter grinder for espresso?

Often not, and the reason is the adjustment range rather than the quality. Many grinders built for filter coffee cannot physically close their burrs far enough to reach the 200 to 400 micron range espresso needs, so the finest setting still pours a shot in ten seconds. Even where the range reaches, espresso demands far more consistency than filter does, because at that size the same percentage of particle variation is a much bigger relative error and shows up as channelling. Grinders sold for espresso have both a finer range and finer adjustment between settings, which is what you are paying for.

Does the roast level change what grind setting I need?

Yes, and it catches people out. Darker roasts have lost more moisture and have a more broken down cell structure, so they are more brittle and shatter more easily. The same grinder setting produces a finer grind from a dark roast than from a light one. Switching from a light roast to a dark one usually means going a step or two coarser to keep the brew time the same. Very fresh beans also behave as though they were ground finer, because the carbon dioxide they are still releasing resists the water, which is why espresso from beans roasted three days ago often runs slow.

How long before brewing can I grind coffee?

As close to brewing as you can manage, though how much it matters depends on the method. Grinding multiplies the surface exposed to air, and the volatile aromatic compounds start leaving straight away, with the steepest drop in the first 15 to 30 minutes. Espresso notices within minutes. Filter coffee notices over a few hours rather than immediately. Cold brew barely notices at all, so grinding a batch the night before is fine. Store whole beans rather than ground coffee in an airtight container at room temperature and away from light.

Is a coffee grind size chart accurate?

Only as a rough guide. Published charts disagree with each other by several hundred microns on the same method, and cold brew is the clearest example: Mahlkonig, a commercial grinder manufacturer, puts it at 700 to 900 microns, while many charts say 1,200 to 1,500. Both produce good cold brew, because a long steep is forgiving. Home grinders also do not display microns, and grinder numbering is not comparable between machines, so a setting of 15 means nothing across two brands. Use a chart to know which direction to move and roughly how far, then judge by how the brew runs and how it tastes.

How to Grind Coffee Beans: Grind Size for Every Brew Method

What grind size actually controls

Grinding does two things at once, and almost every grind problem comes from forgetting the second one.

The first is surface area. Breaking a bean into smaller pieces exposes more of its inside to water, so the coffee gives up its sugars, acids and oils faster. Finer grind, faster extraction.

The second is resistance. A bed of fine particles packs tightly and leaves narrow paths between the pieces, so water moves through it slowly. A bed of coarse particles is loose and water pours straight through. Finer grind, slower flow.

Those two effects pull in the same direction, which is why grind size is such a powerful dial: going finer both speeds up extraction and gives the water longer to do it. It is also why grind is the setting to change first when a cup is wrong, ahead of dose, temperature or time.

The job of a brew method is to balance the two. Espresso needs enough resistance to hold back nine bar of pressure for around 25 seconds. A French press has no resistance to manage at all, because the water simply sits there, so the grind only has to control how fast the coffee gives itself up over four minutes. Every method between those two is some mix of the same trade.

Grind size by brew method

ESPRESSO, fine. Roughly 200 to 400 microns. It should look like table salt and feel slightly powdery when you rub it, but you should still be able to feel individual grains rather than flour. This is the least forgiving size on the list: a change of a few tens of microns moves the shot time by several seconds.

MOKA POT, fine to medium-fine. Finer than filter, coarser than espresso. The pressure is somewhere around one to two bar rather than nine, so it needs less resistance than espresso and would choke on a true espresso grind. Do not tamp it.

AEROPRESS, anywhere you like, which is genuinely the answer. The short contact time and the paper filter make it the most flexible brewer most people own. Fine and quick gives you something espresso-adjacent, medium and steeped for two minutes gives you a filter cup.

POUR OVER AND FILTER, medium. Roughly 500 to 800 microns, around the texture of coarse sand or granulated sugar. This is the setting most home grinders are built around, and the one where a grinder's weaknesses show up least.

FRENCH PRESS, coarse. Roughly 800 to 1,000 microns, closer to coarse sea salt or breadcrumbs. Too fine and the fines slip past the mesh and settle in your cup as sludge, which is the single most common French press complaint.

COLD BREW, coarse. Here the published charts disagree with each other, which is worth knowing rather than glossing over. Mahlkonig, who make the grinders a lot of cafes use, put cold brew at 700 to 900 microns, finer than their own French press figure. Plenty of other charts say 1,200 to 1,500. Both work, because a 16 hour steep is forgiving enough that the grind is not the variable deciding your cup. Start at French press coarse and go coarser if it tastes heavy or muddy.

Treat all of these numbers as landmarks rather than targets. No home grinder has a micron readout, published charts disagree by several hundred microns on the same method, and the grind that suits your beans, your water and your brewer sits somewhere in a range rather than on a point.

How to judge grind size without a micron reading

You have two instruments: your eyes and your fingertips. Both are better than people expect once you know what you are looking for.

BY EYE, spread a spoonful on a white plate or a sheet of paper and look at it in good light. What you want to see is grains of roughly one size. What tells you something is wrong is a mix: visible chunks sitting in a bed of powder means the grind is uneven, and that is a grinder problem rather than a setting problem. The household comparisons run flour, table salt, sand, granulated sugar, coarse sea salt, breadcrumbs, from finest to coarsest.

BY FEEL, take a pinch and rub it between finger and thumb. Espresso grind feels like it wants to clump and leaves a faint film on your skin. Filter grind feels gritty and separate, like fine sand. Coarse grind feels like small hard pieces you can count. If a supposedly fine grind feels smooth and soft with no grain to it at all, you are into flour territory and the shot will choke.

THE CLUMP TEST is the useful one for espresso. Squeeze a small amount in your palm. Espresso grind holds together in a loose clump for a moment and then falls apart. Filter grind will not hold at all. Anything that stays packed like wet sand is too fine.

Do this on the same plate under the same light each time and you will build a reference faster than any chart can give you. Photographs of grind size are close to useless, because scale and lighting are doing most of the work in them.

Reading the cup: finer or coarser?

The cup tells you which way to move, and the rule is short enough to memorise: sour means go finer, bitter means go coarser.

Here is why. The compounds in coffee do not come out all at once. Acids come out first, sugars next, and the bitter and drying compounds last. Stop too early and you have the acids with nothing to balance them, which tastes sharp, thin and sour, and often salty. Go too far and you have pulled out the last group, which tastes bitter, dry and hollow. The Specialty Coffee Association puts the useful window at 18 to 22 percent of the coffee's mass dissolved into the water, and grind size is the main way you move within it.

So a sour cup means the water did not get enough out, and grinding finer gives it more surface to work on and more time to work. A bitter cup means it got too much, and grinding coarser pulls it back.

The confusing case is a cup that is sour AND bitter at the same time. That is not a grind size problem and going finer or coarser will not fix it. It means your grind is uneven, so some particles are over-extracting while others are under-extracting in the same brew. That points at the grinder rather than the dial, and it is the standard signature of a blade grinder.

Use time as a second instrument, because it is objective in a way that taste is not. A double espresso should take roughly 25 to 30 seconds to pour after the pump starts. A pour over should finish draining in about three to four minutes for a single cup. If your shot runs in 15 seconds, you know the grind is too coarse before you taste anything. If your pour over stalls at six minutes, it is too fine.

Change one thing at a time and change it by a little. Move the grinder one or two steps, brew again, and taste. Chasing two variables at once is how people spend a whole bag of beans and end up back where they started.

Why the same setting stops working

A setting that was right last month can be wrong today without you touching anything, and knowing the reasons saves a lot of confusion.

ROAST LEVEL. Darker roasts are more brittle, because more of the moisture has been driven out and the cell structure is more broken down. The same grinder setting therefore produces a finer grind from a dark roast than from a light one. Moving from a light Ethiopian to a dark Italian blend usually means going a step or two coarser.

BEAN AGE. Fresh beans, particularly within a week of roasting, are still releasing carbon dioxide. That gas resists water during brewing, so a very fresh coffee behaves as though it were ground finer than it is. Espresso from three day old beans often runs slow and tastes sharp, then settles down by the end of the first week.

HUMIDITY. Ground coffee picks up moisture from the air, and damp grounds clump and pack tighter. In a humid kitchen an espresso grind can run noticeably slower than the same setting did in winter.

GRINDER CLEANLINESS. Old grounds build up around the burrs and inside the chute, and stale oil makes fresh grounds stick to it. The grind gets less consistent and the machine holds back more of what you put in. Our guide to cleaning a grinder covers the routine.

None of these need you to relearn anything. They just mean the dial is a live setting rather than a number you write down once.

What your grinder can and cannot do

Grind size is a setting. Grind consistency is a property of the machine, and no setting improves it.

Burr grinders crush beans between two shaped surfaces set a fixed distance apart, so a particle can only leave when it is small enough to pass through the gap. That is what produces a narrow range of sizes. Blade grinders chop at whatever is in their way, so the pieces near the blade get hit repeatedly and turn to dust while pieces at the edge stay whole. That is the sour-and-bitter cup above, built into the hardware.

The demand a brew method makes of a grinder rises steeply as you go finer. A modest burr grinder makes filter coffee that is hard to distinguish from an expensive one. Espresso is the opposite: at 200 to 400 microns the same percentage of variation is a much bigger relative error, so this is where grinders separate. The Baratza Encore is a well judged filter grinder that is deliberately not built for espresso, while its ESP sibling and the Breville Smart Grinder Pro add the finer adjustment range that espresso needs.

One practical point about adjustment. Stepped grinders click between fixed positions, which makes them repeatable and easy to return to a known setting. Stepless grinders move continuously, which matters for espresso because the right setting often falls between two clicks. For everything except espresso, stepped is fine and arguably easier to live with.

If you have no grinder at all, that is a different question with a different answer, and we have written it up separately in our guide to grinding coffee without a grinder.

How much to grind, and when

Grind by weight rather than by scoops. Beans vary in density by roast level and origin, so a scoop of a light roast and a scoop of a dark roast are not the same amount of coffee, and a cheap kitchen scale removes the whole problem. Our pour over ratio guide covers the numbers for filter brewing; espresso is usually 18 to 20 grams for a double in a standard basket.

Grind immediately before you brew. This is the one piece of received wisdom that holds up completely. Grinding multiplies the surface exposed to oxygen by an enormous factor, and the aromatic compounds that make coffee smell like coffee are volatile, so they start leaving straight away. The drop is steep in the first 15 to 30 minutes and it is easy to taste.

That said, the size of the effect depends on what you are brewing. Espresso notices within minutes. Filter coffee notices over hours. Cold brew barely notices at all, which is why grinding a batch the night before is fine.

Store whole beans in an airtight container at room temperature, out of the light. The freezer is genuinely good for long term storage of beans you are not going to touch for a month, provided the bag is properly sealed and you let it come back to room temperature before opening it, because condensation on cold beans is what does the damage.