CSS clamp() lets a value like font-size scale smoothly between a minimum and maximum as the viewport width changes, without needing multiple media query breakpoints. Writing the underlying math by hand each time is fiddly, so this tool generates it for you.
Set your desired minimum and maximum font sizes along with the viewport width range they should apply across, and the tool calculates the correct clamp() expression using the standard linear interpolation formula.
The live preview text below updates using the generated value, so you can resize your browser window and see the fluid scaling in action before copying the CSS into your stylesheet.
Because everything runs locally in your browser, results appear instantly and nothing you type or upload is ever sent to a server.
Bookmark this page if you expect to use this tool regularly — it loads fast and behaves the same way every time, with no account needed.
This kind of task shows up constantly in everyday writing, coding, design, and admin work, which is exactly why a dedicated, focused tool saves so much back-and-forth.
A tool that does one job well, without a cluttered interface or unrelated features competing for attention, tends to be faster to use than a heavier all-in-one app.
If you find yourself needing this conversion or calculation often, keeping this page open in a tab is usually faster than digging through a bigger software suite's menus.
Frequently asked questions
What does clamp() actually do?
clamp(min, preferred, max) picks the preferred value but never lets it go below the minimum or above the maximum — the preferred value here is a viewport-relative calculation that creates smooth scaling.
Is browser support good for clamp()?
Yes, clamp() is supported in all modern browsers and is a standard, well-established CSS function at this point.