Fluid typography — text that scales smoothly with the viewport instead of jumping abruptly at media query breakpoints — is easy to want and surprisingly fiddly to calculate by hand. The math behind a correct clamp() expression is simple linear interpolation, but getting the vw coefficient and rem offset exactly right takes a few extra steps most people don’t bother with.
What Is the CSS Clamp() Calculator?
Enter a minimum viewport width and size, and a maximum viewport width and size, and the tool instantly computes the exact clamp(min, preferred, max) CSS expression that scales linearly between those two points — with a live preview showing the effect as you resize the browser.
How to Use It
- Open the tool at /tools/css-clamp-calculator.
- Enter your minimum viewport width and the size you want at that width.
- Enter your maximum viewport width and the size you want at that width.
- Choose
remorpxas your output unit. - Copy the generated
clamp()CSS.
Key Features
- Mathematically exact interpolation — verified to hit precisely your minimum and maximum sizes at their respective breakpoints.
- Live preview text that visibly scales as you resize your browser window.
- Choice of
remorpxoutput, matching your project’s conventions. - Pure CSS output — no media queries, no JavaScript, works in every modern browser.
When to Use This Tool
- Building fluid, responsive typography without a wall of media queries.
- Scaling spacing (padding, margin, gaps) smoothly across viewport sizes.
- Learning how the underlying linear-interpolation math behind
clamp()actually works.
Try It Now
Open CSS Clamp() Calculator directly, or press ⌘K and type the tool name from anywhere on the site.
Part of the CSS Tools collection on WebdevToolbox — free, browser-based developer tools with no login required.