CSS clamp() Calculator
Fluid typography without media queries — set the size you want at a small viewport and at a large one, and get the exact clamp() expression with the math explained, a live preview, and a breakpoint table. Everything runs in your browser.
| Viewport | Computed size |
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About this tool
clamp(MIN, PREFERRED, MAX) resolves to the preferred value, but never below MIN or above MAX. For fluid sizing, the preferred value is a linear function of viewport width: the tool computes the slope between your two anchor points, converts it to vw units, and derives the rem intercept — so the size interpolates perfectly between exactly the values you asked for.
Output in rem is recommended: it keeps the formula responsive to the user's font-size preference (assuming the default 16px root). Beware fully vw-only sizes with no rem component — they don't scale when users zoom text; the mixed rem + vw form generated here avoids that when your min/max sizes differ from pure proportionality. Nothing you enter leaves the page.