# clamp() Calculator – CSS Responsive Font Text Size Calculator

## clamp() Calculator for Fonts and Texts

The `clamp()` function in CSS is a way of setting responsive styles based on a range.

## The Result

clamp(1rem, -2.764rem + 16.731vw, 11.875rem)

The browser will choose the `preferred value` unless it’s smaller than the `minimum value` or larger than the `maximum value`, in which cases it will use those boundary values.

## Calculations for Responsive Font Size

1. ### Values you input:

• `minSize`: Minimum font size (px)
• `maxSize`: Maximum font size (px)
• `minViewport`: Minimum viewport size (px) where `minSize` applies
• `maxViewport`: Maximum viewport size (px) where `maxSize` applies
• `rootFontSize`: Usually 16px for most browsers, but can be customized. This is the base size for computing relative units like `rem`.
2. ### Goal:

To find an equation in the format of `y = ax + b` that defines a linear relationship between the viewport size (`x`) and the font size (`y`).

3. ### Calculations:

a: The slope of the line, which represents how much the font size should change for every pixel change in viewport size. It’s calculated using:

``a = (maxSize - minSize) / (maxViewport - minViewport);``

b: This is the y-intercept and it’s found by rearranging the equation `y = ax + b` to solve for `b`. Using the point (`minViewport`, `minSize`), it’s calculated as:

``b = minSize - a * minViewport / rootFontSize;``
4. ### The Result:

The resulting equation `y = ax + b` can be translated into `clamp()` syntax:

``clamp(minSize / rootFontSize rem, b rem + a viewportUnits, maxSize / rootFontSize rem)``

The reason for using a linear relationship between viewport and font size is to ensure a smooth and consistent scaling of the font size as the viewport changes size.

Browser Compatibility: https://developer.mozilla.org/en-US/docs/Web/CSS/clamp#browser_compatibility