responsive. one scale rarely survives both a phone and a 27-inch display. turning responsive on adds a second breakpoint with its own base size and — if you want it — its own ratio, and the CSS export gains a @media block that overrides the same custom properties. the usual move is a bigger base at the same ratio, which is why the breakpoint ratio defaults to inherit. reach for a larger ratio only when the wide layout genuinely needs a louder headline.
fonts.the picker carries a curated shelf of Google families rather than all 1,800 — the ones that actually get used in interface and editorial work. only the family you select is downloaded. weights run 100–900 because that is how designers think, but many families ship four static weights; when the one you pick doesn't exist the control says which weight really renders, and the export agrees with the preview rather than with the input.
the contrast readout under the specimen is the part other scale generators leave out. a 300-weight grey on off-white can look beautiful in a preview and fail WCAG at every size. the ratio is computed the same way the color scheme tool does it — relative luminance, not averaged RGB — and it grades body and headings separately, because they almost never share a weight.
the sample field takes your own copy. leave it empty and the preview falls back to demo lines chosen per size band, so each step shows type doing the job it would actually do.