tags: [] - coffee/brewing - coffee/brewing/filter aliases: - 4:6 Method - 4-6 Method - Tetsu Kasuya method - 4 to 6 brewing method created: 2026-05-10 updated: 2026-05-10

Tetsu Kasuya 4-6 Method¶

Tags: #coffee/brewing #coffee/brewing/filter Aliases: 4:6 Method, 4-6 Method, Tetsu Kasuya method, 4 to 6 brewing method Related: Brewing Methods MOC | Hario V60 | World Brewers Cup Status: ✅ Complete

Overview¶

The 4-6 Method is a structured pour-over brewing technique developed by Japanese coffee professional Tetsu Kasuya, designed for use with the Hario V60. The name refers to a division of total brew water into two phases — the first 40% and the final 60% — each serving a distinct function in the cup. Kasuya used this method to win the 2016 World Brewers Cup in Dublin, Ireland, becoming the first Japanese competitor to win the championship, and the subsequent global adoption of the method established it as one of the most widely taught pour-over frameworks in specialty coffee.

The Method's Logic¶

The 4-6 Method departs from conventional pour-over recipes, which typically treat all pours as interchangeable or gradually varying contributions to a single extraction. Kasuya's framework makes explicit that different pours in a brew serve fundamentally different functions, and it organises those pours accordingly into two distinct phases.

First 40%: Flavour Control¶

The first 40% of total brew water is poured in two separate equal pours. This phase primarily governs the flavour balance of the cup — specifically the balance between acidity and sweetness or body. By adjusting the distribution of water between the two pours within this phase, the brewer can shift the resulting cup profile:

A larger first pour relative to the second emphasises acidity and brightness
A larger second pour relative to the first emphasises sweetness and body

This gives the brewer a direct, reproducible lever for adjusting flavour character without changing the coffee dose, grind size, or total water volume.

Final 60%: Strength Control¶

The final 60% of total brew water is poured in multiple equal pours — typically three — and this phase primarily governs the strength (concentration) of the brew:

More pours within the final 60% (i.e. smaller individual pours) produce a stronger, more concentrated cup
Fewer pours (i.e. larger individual pours) produce a lighter, less concentrated cup

This separation allows the brewer to adjust strength independently of flavour balance, which is a significant practical advantage over recipes where both variables are entangled.

Standard Parameters¶

The standard 4-6 Method parameters as published by Kasuya are:

Coffee dose: approximately 20 g
Total water volume: 300 ml
Brew ratio: approximately 1:15
Water temperature: approximately 93°C
Grind size: medium-coarse
Pour interval: approximately 45 seconds between pours
Total brew time: approximately 3 minutes 30 seconds to 4 minutes
Brewer: Hario V60

Each pour within the first 40% is 60 ml (using equal distribution). Each pour within the final 60% is 60 ml when using three pours. The 45-second intervals allow each pour to drain sufficiently before the next addition.

2016 World Brewers Cup¶

Tetsu Kasuya used this method to win the 2016 World Brewers Cup in Dublin, Ireland, representing Japan. His victory was the first WBrC win for a Japanese competitor and drew immediate and significant international attention to the method. Kasuya published the method openly following the win, making the framework freely available to coffee professionals and home brewers alike.

The win was notable not only as a competition result but as a demonstration that a systematic, teachable framework — rather than an idiosyncratic or talent-dependent technique — could achieve world-championship results in manual brewing.

Educational Significance¶

The 4-6 Method's most significant contribution to specialty coffee practice is pedagogical. Most pour-over recipes available before 2016 described a sequence of pours without explaining what each pour contributed to the final cup. Kasuya's framework made the functional logic of pour sequencing explicit and actionable.

By providing independent levers for flavour balance and strength, the method gave brewers — including those without extensive sensory training — a systematic way to diagnose and adjust their brews. A cup that is too acidic can be corrected by adjusting the first-phase distribution; a cup that is too weak can be corrected by adjusting the final-phase pour count. This diagnostic clarity is unusual among pour-over methods and explains much of the method's rapid uptake.

Coverage by James Hoffmann on YouTube and by coffee forums accelerated the spread of the method globally after the 2016 WBrC, making it one of the most widely discussed and tested pour-over techniques of the following decade.

Variations¶

Brewers have explored a range of variations on the core 4-6 structure:

Adjusted phase ratios (50:50, 30:70) to shift the balance of flavour and strength control
Different numbers of pours within the final 60% phase (two or four pours rather than three)
Scaled total volumes (e.g. 15 g coffee to 225 ml water, maintaining the 1:15 ratio)
Alternative brewers (although the method was designed for the V60 and performs differently on other drippers)

The core principle — that brew water should be divided into functionally distinct phases — remains consistent across these variations.

Key Facts¶

Developed by Tetsu Kasuya, Japanese coffee professional
Used to win the 2016 World Brewers Cup in Dublin, Ireland — first WBrC win for a Japanese competitor
Name refers to division of brew water: first 40% controls flavour balance; final 60% controls strength
First 40%: larger first pour = more acidity; larger second pour = more sweetness and body
Final 60%: more pours = stronger; fewer pours = lighter
Standard parameters: 20 g coffee, 300 ml water (1:15 ratio), ~93°C, medium-coarse grind, ~45 s between pours
Designed for the Hario V60
Method published openly by Kasuya after the 2016 WBrC
Widely adopted globally; became one of the most taught pour-over frameworks in specialty coffee

References¶

This article is part of All-About-Coffee.com - The comprehensive coffee knowledgebase.