Why does my coffee taste bitter? How to fix it

Updated 18 October 2026

Short answer

Bitter coffee is usually over-extracted: the water kept going after the good flavours and pulled out the harsh, late-dissolving compounds. Change one thing per brew, in this order: Grind coarser, then pour lower and gentler, then move some brew water to bypass.

What it means

Bitterness is usually over-extraction. The compounds behind a harsh, lingering bitterness dissolve last, so they only show up in quantity once the water has already taken everything pleasant out of the grounds.

The fix is to extract less: coarser grind, less contact, a gentler pour. Change one thing per brew so you know which one worked.

Pour over: what to change

Pour over (V60, Chemex, Kalita Wave, Origami, Orea). Try these one at a time, in this order — move on to the next only when the one before hasn't fixed it.

1
Grind coarser
Go about 60 µm (2 clicks on a Comandante C40) coarser. Bigger particles and fewer fines mean less surface and a freer flow, so less is extracted — and less of the late-dissolving bitter and drying compounds make it into the cup.
2
Pour lower and gentler
A lower, calmer pour disturbs the bed less, extracts less, and keeps fines from migrating down and clogging the filter.
3
Move some brew water to bypass
Brew with about 10% less water — 225g instead of 250g — and add the difference as hot water afterwards. Less water runs through the grounds, so fewer of the late, bitter compounds come out, and the cup keeps its size and strength.
4
Lower the temperature
About 3°C cooler. Cooler water extracts more slowly — a gentler change than grind, so try it once grind and time have had their turn.

Immersion: what to change

Immersion (AeroPress, French Press, Hario Switch). Try these one at a time, in this order — move on to the next only when the one before hasn't fixed it.

1
Grind coarser
Go about 60 µm (2 clicks on a Comandante C40) coarser. Bigger particles and fewer fines mean less surface and a freer flow, so less is extracted — and less of the late-dissolving bitter and drying compounds make it into the cup.
2
Shorten the steep
Press, plunge or open the valve about 15 seconds sooner, so the water has less time to reach the slow-dissolving bitter compounds.
3
Agitate less
Fewer stirs, or none after the bloom. Stirring speeds extraction, and it also churns fines into suspension.
4
Move some brew water to bypass
Brew with about 10% less water — 225g instead of 250g — and add the difference as hot water afterwards. Less water runs through the grounds, so fewer of the late, bitter compounds come out, and the cup keeps its size and strength.
5
Lower the temperature
About 3°C cooler. Cooler water extracts more slowly — a gentler change than grind, so try it once grind and time have had their turn.

Cold brew: what to change

Cold brew. Try these one at a time, in this order — move on to the next only when the one before hasn't fixed it.

1
Grind coarser
Go about 60 µm (2 clicks on a Comandante C40) coarser. Bigger particles and fewer fines mean less surface and a freer flow, so less is extracted — and less of the late-dissolving bitter and drying compounds make it into the cup.
2
Steep for less time
Cut the steep by about 12.5% — two hours off a 16-hour steep.

Worth knowing

Some bitterness belongs to the coffee. Darker roasts carry roasty bitterness however carefully you brew them — if the rest of the cup is sweet and balanced, it may just be the bean.
Bitter with a very slow drawdown on a pour over points at the grind choking the bed. Coarser is still the answer; it fixes both.

Change one thing at a time

It's tempting to grind finer and raise the temperature and pour differently. Then the next cup is better or worse and you don't know why. One change per brew is slower on paper and much faster in practice. The full dial-in guide covers the order to fix things in when there's more than one problem.

Questions