What’s The Best Coffee Grind Size For A French Press?

Just got a French press and want to know what kind of coffee grind setting you should use? That’s what we’ll get into in this article.

The best grind size for a French press is medium-coarse. This is a size similar to normal table salt. This grind size can easily be filtered out by a French press filter while not taking too long to brew. A grind that’s too coarse can brew watery/sour coffee while a smaller size becomes bitter.

Here’s why that is the case and what you can do if you don’t have the right grind size at the moment.

Best French press grind size

The best grind size for a French press is medium-coarse. This is a size that’s comparable to normal table salt. This grind size will give the best-tasting coffee while not becoming too bitter.

The grind size is the average size of the coffee particles after grinding up the whole beans. If you buy pre-ground coffee, there isn’t much you can do about changing this but it’s still important to get the right size otherwise your coffee might not be all that good.

Not sure how to exactly make good coffee in a French press? Click here for my step-by-step guide.

If you have a half-decent grinder, it will be possible to adjust the size. Don’t want to spend too much to try out grinding your own coffee? Check out the Hario Slim on Amazon. It’s adjustable, compact and affordable. If you want something that is higher quality and produces good grinds the TimeMore C2 (Amazon) is a good option.

Different grind sizes work best for different brewing methods. An espresso machine works best when using very fine coffee grounds, most drip methods use around a medium size and a French press prefers a medium-coarse size.

There are two big reasons why a French press works better with that coarser size;

• Metal filter
• Steep time

Metal filter

The biggest reason for the larger than usual grind size in a French press is the design of the brewer itself. French presses have a metal filter screen. Metal filters in a French press are pretty fine but nowhere near as fine as a paper filter for example. You push down the plunger to filter the grounds out of your brew. That means those grounds have to be large enough to be caught by this filter.

But an espresso machine use a metal filter? Why does that use a fine grind? Well, an espresso machine has much smaller holes in the filter basket. This will keep in the finer grounds. However, it makes it harder to get the water through the puck. That’s why an espresso machine uses up to 9 bar of pressure to push the water through the grounds and filter. There is no way you can do this with a French press.

If the filter in your French press was fine enough to use an espresso grind, you wouldn’t be able to actually push down the plunger because it just takes more pressure than you can create.

Suggested: Why is my French press coffee watery?

Steep time

A French press is an immersion brew method. That means the grounds and water hang out together for a while before being filtered. The longer you steep the coffee, the stronger it becomes. So while the grinds have to be coarse enough to be caught by the filter, they have to be fine enough to get the coffee strong enough in a reasonable amount of time.

The finer grounds are, the more surface area a certain amount of coffee has. More surface area means more places for the water to interact and thus the coffee brews faster. So in a French press, you have to balance the size the filter can deal with and how long you want to wait for your coffee to be done. The best compromise for a French press is the medium-coarse grind.

That also means you can play around with the size to influence the brew time and therefore taste.

Suggested: Why is my French press coffee bitter?

Adjusting grind size

Maybe you’re not happy with the results you’re currently getting from your French press. Adjusting the grind size is one of the big factors that will impact the taste and strength of your brew (steep time is another big one).

Getting a hand grinder with an adjustable grind size doesn’t have to be very expensive. I’m using the Hario Skerton+ (Amazon link) And I like my results with a French press. However, it does produce a bit of fines which is what leaves the sediment in your cup. A good upgrade from there is the TimeMore C2 (Amazon link) which grinds much more consistently.

So changing the size slightly can have the effect you’re looking for. Always make small adjustments and see if you like the change. Try to keep all the other factors the same.

Here’s what you might want to improve and how to adjust the grind size;

• French press coffee too bitter: Grind the coffee slightly bigger.
• French press coffee too watery: Grind the coffee smaller
• French press coffee sour: Grind the coffee smaller
• Too much sediment in cup: Upgrade grinder, French press or filter out fines. Filtering the coffee through a paper filter after brewer will filter all the sediment out but it will also change the taste.

Suggested: Should you push a French press plunger all the way down?

Can you use fine pre-ground coffee in a French press?

What if you get pre-ground coffee because you don’t have a grinder at home?

In the first place, I would recommend anyone who cares about the taste of their coffee enough to read this post should get a coffee grinder (a decent hand grinder will only cost $40) and a bag of whole beans. This will improve your coffee more than you might think.

If you buy pre-ground coffee there are two options;

• Supermarket/convenience store: Here you get coffee from a few big brands. These coffees are blended and ground to appeal to the most people possible. That’s not necessarily a bad thing because it allows more people to have coffee for an affordable price. However, it’s also blended and ground to use the brewing methods the majority uses.
• Local coffee roaster: If you have a local coffee roaster that sells coffee. This is usually fresher and can be ground to suit your needs. It’s often a bit more expensive but you get a higher-quality product that has the grind size you need. And not to mention you support local small businesses this way.

Most people go to the supermarket or a similar place to buy their coffee though. These bags of coffee are ground to be used for the most popular brewing methods. While French presses are a relatively popular way of making coffee for people who care the vast majority of people use a drip coffee maker.

The grounds for drip coffee are a bit finer than is good for a French press. Also, avoid bags that are marketed as ‘espresso’ coffee completely. Espresso coffee is ground even finer than drip coffee.

But can you use drip coffee grounds for a French press? Of course you can and it’ll brew something like coffee but it won’t have the best results. There are a few things you can do to get something a little better though;

• Steep shorter: The biggest thing to change is to steep your coffee a bit shorter. Because the particles are finer, they’ll extract faster. With a medium-coarse grind, a 4-6 minute steep time works for me. With a medium (drip) grind, start at 3 minutes and adjust from there.  
• Use cooler water: Let your water cool down for a little bit (about 1 minute) after it comes off the boil. Cooler water tends to have less bitterness. Click here to find out more about French press and water temperature.

However, you’ll get the best results by using whole beans and grinding them at home just before using the grounds. If you buy a hand grinder, you’ll massively improve the taste of your coffee and it just takes a few minutes extra. A good hand grinder isn’t too expensive and will last you for a long time. The Timemore C2 is a great option if you want a high-quality hand grinder that is very adjustable and grinds consistently.