The tool first separates accents from their letters and discards them, so é becomes e, then maps ß to ss, æ to ae, ø to o, đ to d and ł to l. Apostrophes are deleted, so don't becomes dont. Every other run of characters that is not a letter or digit, such as spaces, punctuation and symbols, becomes a single separator, and separators at either end are trimmed.
For How to Make Café Crème at Home! the results are:
- Default:
how-to-make-cafe-creme-at-home - With Remove stop words:
how-make-cafe-creme-home - With Underscore and Keep letter case:
How_to_Make_Cafe_Creme_at_Home - With Max length 20:
how-to-make-cafe
The stop word list is fixed: a, an, the, and, or, but, of, on, in, at, to, for, with, by, from, is, are, was, were, be, this, that, it and as. When a length limit applies, the slug is cut and then trimmed back to the last separator, so a word that ends exactly on the limit may be dropped. Allow a character or two extra if that matters.
Two more titles show the mapping. Crème Brûlée & Cheese becomes creme-brulee-cheese, since the ampersand is dropped as punctuation. Ærø Ørsted: 10 tips becomes aero-orsted-10-tips, with the digits kept. Capital letters survive only when Keep letter case is ticked.