The wealth of feminine hygiene products available make all sorts of promises. Many brands do list the length of the product as a selling point, with 35cm to 42cm being on one end of the spectrum, but it is the ones which do not list a specific length which are the problem.
Many brands now offer helpful charts to show relative lengths of their products, but there is no context beyond that. A specific product may offer more area than others in the family, but without knowing the actual length, it is hard to tell if they are going to be much more useful than buying the shortest or longest products of that family.
Following are some approximate lengths, measured from end to end*:
18cm: Kotex fresh liners, longer & wider version, which comes in lime green packaging.
21cm: Laurier Active Day Double Comfort Super Slim with non wing/with wings, purple packaging
22cm: Charm Body Fit Extra Maxi, orange packaging
Brands which state the length include:
19cm: Poise Long Liners. These are actually for leaks but were sold in the same section so got picked by mistake.
25cm: Laurier Active Day Super Maxi
26cm: Sofy Extra Dry Skin Comfort Ultra Slim 0.1
28cm: Kotex Overnight with ProActive Guards
29cm: Sofy Side Gathers with Butterfly Hip Guard
30cm: Laurier Ultra Gentle
32cm: Kotex OVERNIGHT (wing)
35cm: Charm Body Fit Night Wing (Charm and Sofy have the same parent company)
35cm: Sofy Body Fit with Butterfly Hip Guard
35cm: Sofy Side Gathers with Butterfly Hip Guard
Utility also depends on various other factors, such as whether the packaging is easy to open, quality of the adhesive, and absorbency; but to me length is the no. 1 contributor to peace of mind.
This post will be updated as more products are encountered.
*Usable area would be 0.5cm less than this number.
*Whisper or Always and Carefree are not listed as I seem to have an allergy to these brands.