How we rate immersion brewers

Immersion is the most forgiving way to brew, so the filter and the vessel do most of the differentiating: paper for a clean cup, metal or cloth for body.

What we can actually read: Filter type and whether a reusable exists are published, as is the material the brew sits in. Actual extraction is not measurable from a spec sheet.

Scored from figures that predict it, because the thing itself is not published.

The 4 rules below score this criterion out of 10, and they add up to 10 exactly. That result is then worth 26 of the category's 100 points.

• Filter3.5 of 10

  paper, micro

  3.5 pts

  metal, mesh

  2.5 pts

  cloth

  2 pts

• Reusable filter offered2 of 10

  present

  2 pts

• Brew volume3 of 10

  240 ml or less

  2 pts

  over 240 ml, up to 500 ml

  2.5 pts

  over 500 ml

  3 pts

• Body material1.5 of 10

  Also read under Build Quality & Seal and Portability, which asks a different question of the same fact.

  stainless, glass, polypropylene, tritan, silicone

  1.5 pts

  plastic

  1.2 pts

10 of 10

These get carried, dropped and packed. Whether the body is glass or a plastic that survives a rucksack is most of the answer.

What we can actually read: Material, replacement parts and warranty are published.

Scored directly from published figures.

1 of the 3 rules below are struck through in this category, because too few makers publish the input. The 2 that remain score this criterion out of 10 between them: a struck rule leaves the sum entirely rather than counting as a zero. That result is then worth 22 of the category's 100 points.

• Material4 of 10

  Also read under Brew Quality & Filtration and Portability, which asks a different question of the same fact.

  stainless

  4 pts

  glass, polypropylene, tritan, silicone

  3.5 pts

  plastic

  2.5 pts

• Replacement parts soldnot scored here

  Fewer than one maker in four publishes this here, so its 3 points leave the sum rather than being guessed at.

  present

  3 pts

• Warranty3 of 10

  1 yr or less

  1.5 pts

  over 1 yr, up to 2 yr

  2.5 pts

  over 2 yr

  3 pts

10 of 10

Parts count is the honest measure here. A four-part brewer is washed in seconds; a siphon is an evening's commitment.

What we can actually read: Parts count, dishwasher safety and published brew time are all stated.

Scored directly from published figures.

2 of the 3 rules below are struck through in this category, because too few makers publish the input. The one that remains scores this criterion out of 10 between it: a struck rule leaves the sum entirely rather than counting as a zero. That result is then worth 20 of the category's 100 points.

• Dishwasher safe4 of 10

  yes

  4 pts

  top rack

  3 pts

  no

  1 pt

• Parts to washnot scored here

  Fewer than one maker in four publishes this here, so its 4 points leave the sum rather than being guessed at.

  3 or less

  4 pts

  over 3, up to 6

  3 pts

  over 6

  2 pts

• Brew timenot scored here

  Fewer than one maker in four publishes this here, so its 2 points leave the sum rather than being guessed at.

  120 s or less

  2 pts

  over 120 s, up to 300 s

  1.5 pts

  over 300 s

  1 pt

10 of 10

The reason many of these exist. A brewer that packs flat with its own case is a different product from one that needs a shelf.

What we can actually read: Travel case, weight and material are published.

Scored directly from published figures.

1 of the 3 rules below are struck through in this category, because too few makers publish the input. The 2 that remain score this criterion out of 10 between them: a struck rule leaves the sum entirely rather than counting as a zero. That result is then worth 18 of the category's 100 points.

• Travel case included4 of 10

  present

  4 pts

• Weightnot scored here

  Fewer than one maker in four publishes this here, so its 4 points leave the sum rather than being guessed at.

  350 g or less

  4 pts

  over 350 g, up to 700 g

  3 pts

  over 700 g

  1.5 pts

• Drop resistance2 of 10

  Also read under Brew Quality & Filtration and Build Quality & Seal, which asks a different question of the same fact.

  polypropylene, plastic, tritan

  2 pts

  stainless

  1.5 pts

  glass

  0.5 pts

10 of 10

Points per pound against the category median.

What we can actually read: Needs a published price here and on at least three rivals.

Computed from price, not from a rule list

Value is the only criterion here with no thresholds of its own, because it cannot be read off one product. It asks what else the same money buys in this category, so it needs the category. That result is then worth 14 of the category's 100 points.

Points already earned on everything else

out of 10

Multiplied by the category median over this price

median ÷ price

Capped at

10

No price published, or fewer than 3 priced rivals

5 of 10

Half marks is not a verdict, it is a refusal to guess: with nothing to compare against, a product is neither good value nor bad, and scoring it either way would invent a finding. It corrects itself as the category fills.