Scalewright

Scalewright calculates a type scale and a spacing scale together, from a base size and a ratio at both a small and a large viewport. It previews every step with your own font, loaded from a URL or a local file, and outputs fluid CSS clamp() values, a Tailwind config and Figma variables for each breakpoint.

It's best for front-end developers setting up a new site and designers who want headings that scale smoothly between phone and desktop instead of jumping at breakpoints. Free, no account needed. The caveat: fluid values are calculated for viewport width only, so it doesn't help with container-based layouts, and line-height suggestions are basic.