Filter brewing
Dialling in filter coffee
Hold the ratio, change the grind, and use total brew time to tell you whether the change landed.
- Skill level
- Beginner
- How long it takes
- Two or three brews for a new coffee
- Equipment needed
- Burr grinder, Digital scale, Pour-over dripper
- Steps
- 5
Why it works this way
Filter dialling in works on the same principle as espresso and with much larger steps. The ratio sets strength; the grind sets extraction. Brew time is the reading that tells you the grind moved — a brew that finishes far too quickly did not extract enough regardless of how it tastes, and one that stalls has gone too far. The advantage over espresso is that filter brewing is forgiving enough to make each change legible without needing to be perfect at everything else first.
What you need
Helpful, not essential
How to do it
Fix a ratio and keep it — a common starting point is around 60 g of coffee per litre of water.
Ratio is a strength control. Changing it while chasing extraction confuses the two.
Brew, note the total time from first pour to last drip, and taste.
The time is a property of the grind and the bed, and is the most useful single reading you have.
Sour, thin or finishing very fast: grind finer.
Finer coffee slows the flow and extracts more.
Bitter, drying or stalling: grind coarser.
A stalled bed is over-extracting the part of the coffee the water can still reach.
Only when it tastes balanced, adjust the ratio for strength.
Balanced but weak means more coffee, not a finer grind. Separating the two questions is the whole method.
How to tell it worked
A cup that is sweet and clearly flavoured, without sharpness at the front or dryness at the finish.
If it did not work
What you saw, what to change, and why the change works.
Balanced but too weak
Change: Increase the dose at the same grind.
Strength is a ratio question; extraction is a grind question.
Strong but harsh
Change: Coarsen the grind before reducing the dose.
Harshness is usually over-extraction rather than too much coffee.
Time varies wildly between identical brews
Change: Look at pouring technique and bed disturbance before the grinder.
An uneven bed changes flow more than a small grind change does.
Common mistakes
Changing grind and ratio together
No way to attribute the result.
Instead: One at a time.
Making espresso-sized grind steps
The brew barely changes and the process feels futile.
Instead: Filter needs noticeably larger steps.
Diagnose a specific problem
The science behind it
- Extraction
How much of the coffee's flavour has actually dissolved into the water — too little tastes sour or thin, too much tastes bitter or harsh.
- Strength (intensity)
How concentrated a brew tastes — separate from how it was extracted.
- Contact time
How long water and coffee grounds are actually in contact during brewing.