The AeroPress® was invented by Alan Adler, a Stanford engineer who also designed the Aerobie flying ring. He was not trying to make a design object. He wanted a single good cup of coffee, quickly, without the bitterness he was getting from drip machines.
What he built turned out to be the most versatile brewer in coffee. It is an immersion brewer and a pressure brewer at the same time, it is nearly indestructible, it cleans up in five seconds, and it has its own world championship. It is also the brewer that is hardest to get genuinely wrong.
Classic or inverted?
There are two ways to use an AeroPress®, and the internet has been arguing about them for fifteen years.
Classic (chamber on the cup)
The way it comes in the box. The chamber sits on your cup, coffee goes in, water goes in, you press. Some water drips through during the steep, which shortens your effective brew time slightly - insert the plunger a centimetre to create a seal and it mostly stops.
It is stable, it cannot spill, and it is the method we recommend for anyone starting out.
Inverted (chamber upside down)
You build the brew with the AeroPress® standing on its plunger, then flip the whole thing onto your cup when it is time to press. Nothing drips through, so you get exact control over steep time.
The cost is that you are flipping a chamber of hot water over a cup. Do it over a sink until it is second nature.
The truth is that the difference between the two is far smaller than the difference your grinder makes. Start classic.
The recipe explained
16 g of coffee to 240 g of water is 1:15 - a touch stronger than a pour over, because the short contact time extracts less.
| Style | Coffee | Water | Time | Result |
|---|---|---|---|---|
| House recipe | 16 g | 240 g | 1:30 | A full mug, drink as is |
| Concentrate | 18 g | 120 g | 1:30 | Dilute with 120 g hot water or milk |
| Espresso-style | 20 g | 70 g | 1:00 | Short, intense, for iced drinks |
| Long and light | 14 g | 250 g | 2:00 | Delicate, tea-like, for light roasts |
90 ºC is lower than most filter recipes on purpose. The AeroPress® holds its heat well and the short steep is quite efficient, so boiling water tends to push the cup towards bitterness. For very light roasts, go up to 94 ºC.
Grind size
Medium-fine, like fine table salt - finer than a V60, much coarser than espresso.
Because you are pressing by hand, grind size also controls how hard the press feels. If you are leaning your whole body weight on the plunger, your grind is too fine. If it drops through with almost no resistance, it is too coarse. A press that takes about 30 seconds of steady, comfortable pressure is right.
A hand grinder like the Porlex Mini is the natural partner here - both fit in the same bag, which is the entire point of the AeroPress®. More on grinding in The Basics: Grind Your Coffee Right.
Troubleshooting
| Problem | Likely cause | Fix |
|---|---|---|
| Bitter, harsh finish | Pressed past the hiss, or water too hot | Stop at the hiss; drop to 88 ºC |
| Sour and thin | Under-extracted | Grind finer, or steep 30 s longer |
| Press is very hard | Grind too fine | Grind coarser - never force it |
| Plunger slides down with no resistance | Grind too coarse | Grind finer |
| Water leaks around the seal | Rubber seal worn or dry | Replace the silicone seal - it is a consumable |
| Grounds in the cup | Filter shifted or cap not tight | Rinse the filter to stick it in place; tighten fully |
The hiss at the end of the press is air, not coffee. Everything you push through after it comes from the driest, most over-extracted part of the puck.
Paper or metal filter?
The stock paper micro-filters give a clean cup with no sediment and no oils - closer to a pour over. They cost almost nothing and you can rinse and reuse one several times if you want to.
A metal filter lets the oils and some fine sediment through, giving a heavier, rounder cup closer to a French press. Neither is better. Paper for clarity, metal for body.
Which coffee to use
This is the brewer that handles anything. Light and fruity, dark and chocolatey, decaf - the short contact time and paper filter keep almost every coffee tasting reasonable.
If you want the AeroPress® to really sing, use a bright filter roast and the long-and-light recipe above. If you want a comforting morning mug, a chocolatey espresso roast brewed as a concentrate with hot milk is hard to beat.
AeroPress® questions, answered
What grind size for AeroPress®?
Medium-fine, about the texture of fine table salt. It should press with steady, comfortable pressure over roughly 30 seconds - if you are straining, grind coarser; if the plunger drops freely, grind finer.
What is the AeroPress® coffee-to-water ratio?
1:15 for a full mug - 16 g of coffee to 240 g of water. For a concentrate to dilute with water or milk, use 18 g to 120 g and add hot water afterwards.
Is inverted better than classic?
Not meaningfully. Inverted gives you exact control over steep time because nothing drips through, but the difference in the cup is much smaller than the difference a burr grinder makes. Classic is safer and we recommend starting there.
Does the AeroPress® make espresso?
No. Real espresso needs about 9 bars of pressure; an AeroPress® produces well under one. It makes an excellent concentrated coffee that works in milk drinks, but it is not espresso and will not behave like it.
Why does my AeroPress® coffee taste bitter?
The most common cause is pressing past the hiss at the end. That last push forces water through the most over-extracted part of the puck. Stop the moment you hear air, and try dropping your water to 88 ºC.
Can I reuse AeroPress® paper filters?
Yes. Rinse one under the tap after brewing and it will happily do three or four brews. Replace it once it starts to look grey or brews noticeably slower.
How much coffee is in one AeroPress®?
One brew makes about 240 ml with our house recipe - a standard mug. The chamber holds roughly 250 ml, so for two people brew a concentrate and dilute, or simply brew twice.
Keep going
The AeroPress® is the brewer to own if you only own one. When you want more clarity and control, the V60 is the next step. When you want to brew for a table rather than a mug, use the Chemex®.
Everything here assumes fresh coffee. We roast to order in Lisbon and ship within 24-48 hours - or let the subscription keep a bag arriving on your rhythm, ground for the AeroPress® if you want it that way.
