Methodology
Every number carries a mark showing where it came from: measured by us, published by the maker, derived arithmetically from other published figures, or a category default. Nothing is estimated silently and no cell is filled with a plausible guess. A blank cell means nobody publishes that figure.
Where figures come from
- Measured
- Taken from a physical unit.
- Maker
- Published by the brand or a retail listing. Not independently verified.
- Derived
- Calculated from other published figures — a unit conversion, or capacity divided by flow rate. Arithmetic, not measurement.
- Default
- Nobody states it. The category default is shown instead. Currently used only for country of manufacture.
- Not published
- Nobody states it and there is no defensible default. Shown as an empty cell, never as a zero.
Why unstated country of manufacture is recorded as China
Manufacture outside China is a selling point, and brands that have it say so. In this database, the two products not made in China — one made in Spain, one in Connecticut — both print it on the packaging and in the listing title. Every other maker is silent.
Recording that silence as "not published" would be technically accurate and practically useless: it would leave the column almost entirely empty while the answer is knowable. So silence is recorded as China and marked as a default, not as a fact. If a brand tells us otherwise, the figure changes and the mark changes with it.
Note that "Designed in Germany", "Developed in the USA" and a European head office address are not manufacturing claims, and are not treated as such here. Nor is a seller-entered country-of-origin field on a marketplace listing.
Pressure: the figure nobody publishes
Portable bidets are sold on pressure. "High pressure" appears in the product title of most listings in this category. Across every brand in this database, exactly one publishes a pressure figure in any unit.
The pressure and spray-distance rows stay in the table anyway, almost entirely empty, because that emptiness is the single most useful thing this database currently shows. Spray distance — how far the jet carries, measured horizontally — is the practical stand-in, since anyone can reproduce it with a tape measure. The three figures presently in that row were measured by Treeline Review, not by us, and are credited on the product pages.
Environmental score
Computed from published specs only. Three components, 100 points:
| Component | Points | How it is scored |
|---|---|---|
| No battery to discard | 40 | Full marks with no cell at all. A rechargeable pack scores 10 — it is e-waste once, at end of life. Disposable cells score 0, being thrown away continuously. |
| Water per session | 35 | Linear on tank capacity: 250 ml or less scores full marks, 1500 ml or more scores zero. A bottle-cap nozzle scores 30, since you control the volume yourself. |
| Spray time per fill | 25 | Linear against a 120 s reference. More spray time per fill means fewer refills for the same result. |
The denominator is always 100, never just the components a product happens to publish. A component the maker does not publish earns nothing. This is deliberate: scoring against available components only would hand a perfect score to any brand that publishes nothing at all, which would reward exactly the behaviour this site exists to expose.
Use-case rankings
Each "best for" page weights a handful of criteria and publishes the weights on the page. The criteria are built only from fields makers actually publish — a ranking weighted on pressure would be a ranking of one product.
A ranking is withheld entirely below three qualifying products. Below that threshold a leaderboard reports on which brands publish specifications rather than on which product suits the job, and the page says so instead of ranking anyway. Those pages are also kept out of search indexes until they fill in.
Where the criteria come from, and who measured what
Several of the criteria used across this site follow the ones Treeline Review established when two testers took nine backcountry bidets down the Appalachian Trail: spray distance in place of an unpublished pressure figure, bottle-thread compatibility, one-handed operation, and packed weight. Theirs is the only published methodology in this category that involved measuring anything.
Every spray-distance figure in this database is their measurement, not ours, and is credited on the product page it appears on. Their criteria were designed around bottle-cap nozzles, so this site extends them to the mechanisms they did not test — pressurised tanks, electric pumps and reservoir-and-hose units — where spray time per fill and water cost per second of jet matter more than they do for a nozzle screwed onto your own bottle.
Two ways to compare, deliberately kept apart
Use-case pages put every mechanism in one race: a 12 g bottle cap against a 2.5 L bucket, because people really do choose between them. Mechanism pages hold the mechanism constant and ask a narrower question — given that you want a squeeze bottle, which one. Trade-offs that dominate the first comparison drop out of the second.
Three of the five mechanism classes contain only two products. Those pages render as a head-to-head rather than a ranked list, because two products presented as a leaderboard misrepresents the size of the field.
What this site does not do
- It does not publish a figure it cannot link to a public source.
- It does not use star ratings or aggregated review scores.
- It does not resolve contradictions silently. Where two sources disagree, both are shown and the disagreement is flagged on the product page.
- It does not treat "high pressure" or "powerful jet" as data.
- No placement is for sale, and no product is ranked higher for paying.