The Tetsu Kasuya 4:6 method
Split your water into 40% for taste and 60% for strength, then adjust each half on its own. Full numbers for a 20 g to 300 g brew, with ways to bias sweeter or stronger.
The 4:6 method comes from Tetsu Kasuya, the barista who won the 2016 World Brewers Cup with it. Its appeal is that it splits one decision (how should this taste) into two separate, controllable knobs. You divide the total water into two blocks: the first 40% sets the balance between acidity and sweetness, and the last 60% sets the strength. Once you see the water that way, dialing a V60 stops feeling like guesswork.
The two blocks: 40% for taste, 60% for strength
Start with a clean recipe most people can hit: 20 g of coffee, 300 g of water, a 1:15 ratio. Grind a touch coarser than your usual single-cup V60 grind, because the method uses long gaps between pours and you want flow that doesn’t choke. Water around 92 to 94 C (198 to 201 F) for a medium roast; go hotter for light, cooler for dark.
Of the 300 g, the first 40% (120 g) goes in as two pours and decides flavor balance. The last 60% (180 g) goes in as one, two, or three pours and decides how strong and how thick the cup lands. The two blocks act almost independently, which is the whole point: change one without disturbing the other.
Why the first 40% controls taste
The earliest water through the bed pulls the most soluble, brightest compounds first: fruit acids and sugars. By splitting that 120 g into two distinct pours with a pause between them, you choose where the balance sits.
- More water in the first pour, less in the second, leans brighter and more acidic.
- Less water in the first, more in the second, leans sweeter and rounder.
A 50/50 split (60 g + 60 g) is the neutral, balanced default. To go sweeter, try 50 g then 70 g; for more acidity, 70 g then 50 g. You are not pouring more total water, just shifting it within the same 120 g, so extraction barely moves while the flavor profile does.
Why the last 60% controls strength
The remaining 180 g is mostly about how much coffee you wash out of an already-opened bed, which sets concentration and body. Here the lever is the number of pours, not the split between taste and strength:
- Fewer, larger pours (say 2 pours of 90 g) mean less agitation and a shorter total drawdown: a milder, lighter cup.
- More, smaller pours (3 pours of 60 g) keep the bed agitated and the contact time longer: a stronger, heavier cup.
So strength scales with how finely you chop up that 60% block.
Full recipe: 20 g to 300 g, balanced and sweet
Here is the standard 5-pour version (balanced taste, medium strength). Pour each addition over about 10 seconds, then wait until the next time mark. Total brew time lands around 3:00 to 3:30.
| Pour | Cumulative water | Pour at | Block |
|---|---|---|---|
| 1 | 60 g | 0:00 (this is your bloom) | Taste |
| 2 | 120 g | 0:45 | Taste |
| 3 | 180 g | 1:30 | Strength |
| 4 | 240 g | 2:10 | Strength |
| 5 | 300 g | 2:50 | Strength |
Pour 1 doubles as the bloom: 60 g is roughly 3x the dose, plenty to saturate and let the bed off-gas its CO2. Each later pour goes in only once the bed has drained to a flat, soupy surface, not bone dry.
A sweeter, milder cup
Tilt the taste block toward sweetness and cut the strength block to two pours:
- Pour 1: 50 g at 0:00
- Pour 2: 120 g at 0:45 (a 70 g pour)
- Pour 3: 210 g at 1:30 (90 g)
- Pour 4: 300 g at 2:15 (90 g)
Three total pours after the bloom, less agitation: softer, rounder, lower strength.
A brighter, stronger cup
Front-load the taste block and chop the strength block fine:
- Pour 1: 70 g at 0:00
- Pour 2: 120 g at 0:45 (50 g)
- Pours 3 to 5: three even 60 g pours at 1:30, 2:10, 2:50
More early water reads as acidity; the extra strength pours build concentration and a fuller mouthfeel.
Troubleshooting and where it fits
If the brew stalls or runs past about 4:00, your grind is too fine for the long pause structure; coarsen one step. If it gushes through and tastes thin and sour, grind finer or close the gaps between pours slightly. Because the method runs slow on purpose, it is forgiving of a coarse, even grind and pairs especially well with washed light-to-medium coffees where you want to chase clarity.
The honest caveat: 4:6 is a framework, not a law of physics. The two blocks are not perfectly independent, and tiny pour timing differences matter. But as a mental model for which knob to turn, it is one of the most useful things an intermediate brewer can learn.
Next: brew the balanced 5-pour version twice to set a baseline, then change only the first-pour split and taste the difference before you touch anything else. See best-ratio-for-v60 if you want to move off 1:15.