About PeriodFinder
The problem
Period underwear is bought on faith. Absorbency is described in “tampons' worth” - but brands count different tampons, so the same phrase can mean 60 mL at one brand and 100 mL at another. Sizing runs differently everywhere, and because most of it can't be returned once tried, a wrong guess is money in the bin. Shoppers cope with folklore: “size up from your Knix size,” “their Heavy is really a Moderate.”
Nobody neutral had put the brands on one scale. Brands can't compare themselves to rivals, and most comparison articles are affiliate prose without numbers.
What we built
PeriodFinder normalizes every brand's published sizing and absorbency claims onto objective scales: hip inches for size, millilitres for absorbency. Every number is graded A, B, or C for how trustworthy its source is, and carries the date we last verified it - the methodology is public. Two tools do the translating: find my size (one hip measurement, every brand's answer) and the absorbency translator (describe your flow in your own words, get the covering tier in each brand). A live catalog connects the answers to products actually in stock.
Both tools compute in your browser. Your measurements and your flow are never sent to us - by architecture, not policy. How that works.
What this site is not
We publish each brand's own claims, made comparable - not independent lab tests. Where a brand's numbers conflict or can't be confirmed, the grade says so on the number itself. We are not a medical resource: the tools estimate coverage, they don't diagnose. And we will never add cycle tracking or symptom logging - we're a product finder, not a health database.
How we make money
Some outbound links are affiliate links: if you buy after clicking, the brand may pay us a commission at no cost to you. The data never bends to who pays - sizes and millilitres come from published claims and apply identically to every brand, affiliated or not. Full disclosure.
Who stands behind the data
PeriodFinder is an independent editorial project, not a brand's store. The cross-brand absorbency table and the size charts are our own work: we read each brand's published claims, normalize them onto one scale, grade every number for how trustworthy its source is, and date-stamp when we last checked it. The methodology is public, and we correct the table when a brand changes its pages or a reader flags an error - tell us on the contact page and we re-verify against the brand's live pages.
Two promises people often run together: your privacy and our transparency. Your measurements and your flow never leave your browser, by architecture. Who we are and how we built this is the opposite - fully open, on purpose, because a health-adjacent comparison should be checkable. We are a product finder, not a medical service: the tools estimate coverage, they don't diagnose, and anything time-sensitive or medically serious deserves a clinician's input.