How long should coffee brew?

It depends on the method. Use the preset as a starting point, then change one variable at a time. A useful timer is a repeatable reference, not a rule for every coffee.

What should I change if coffee tastes sour or bitter?

Treat sour or bitter taste as a clue, not proof of extraction. Check dose, water, roast and flow, change one variable at a time, then compare with your previous cup.

French Press Brew Timer: 4:00 Steep + 0:30 Press

Start at the first water contact. Use 20 g coffee and add all 300 g water during 0:00–0:30; wait until 4:00, then press gently until 4:30. Four minutes is the time before pressing, not the total. This is an editorial starting schedule.

Use a coarse grind and set the dose first with the French press ratio calculator. If the cup is thin, extend the steep a little on the next brew; if it is dry or bitter, grind coarser before changing the ratio.

French press timing checkpoints

Data table
Phase	Starting time	What to do
Bloom	0:00–0:30	Add all 300 g water and wet the grounds
Steep	0:30–4:00	Keep the lid on and avoid agitation
Press	4:00–4:30	Press slowly, then pour the coffee out

Record the result in the private journal before trying another change. One variable per brew makes the comparison useful.