CH use

CH Units in CSS

CH Units in CSS are a relative measurement unit that is based on the width of the character '0' (zero) of the font being used. This unit is particularly useful when dealing with font-related elements like text, dimensions, and spacing.

How to use CH Units

CH units are used like any other unit in CSS, just replace the unit of measurement with the CH unit. For example, if you want to set the width of a line of text using the CH unit, you would write the following code:
p {
  width: 40ch;
}
This will set the width of the paragraph to 40 times the width of the character '0' of the font being used.

Best Use Cases

CH Units are best used when you need to create a layout that is based on the text or font. They are particularly useful for setting the width of text or containers that hold text. CH units are also helpful for creating responsive layouts that adjust based on the font size. For instance, if the user increases the font size, the element will also adjust accordingly.

Code Snippets

Setting the width of an element using CH units:

div {
  width: 30ch;
}

Setting the font size using CH units:

p {
  font-size: 2.5ch;
}

Setting the line-height using CH units:

p {
  line-height: 1.5ch;
}

Sources

MDN Web Docs
 
CH units are a way to measure things in CSS that are based on the width of a letter. To convert pixels to CH units, you need to know the width of the letter '0' in the font you are using. Then, you can divide the number of pixels by the width of the letter '0' to get the number of CH units. For example, let's say the letter '0' in your font is 10 pixels wide, and you want to set the width of a paragraph to 200 pixels. To convert this to CH units, you would divide 200 by 10, which equals 20 CH units. So you would write width: 20ch; in your CSS code to set the width of the paragraph to 20 CH units.
To find the pixel size of a font's '0', you can use a tool like a browser's developer tools. Open the developer tools and select an element that uses the font you want to measure. Then, navigate to the "Computed" or "Styles" tab and find the "font-size" property. Take note of the font-size value in pixels. Next, create an element that contains only the character '0' in the font you want to measure. Set the font-size of this element to the same value you found earlier. Finally, measure the width of the '0' character using the browser's developer tools or a tool like a screen ruler. The width you measure is the pixel size of the font's '0', which can then be used to convert to CH units.

Uses of CH Units in CSS

CH units are a relative unit of measurement in CSS that are based on the width of the character '0' (zero) of the font being used. Here are five use cases for CH units in CSS, along with code snippets and sources for reference:

1. Setting the width of text

CH units are particularly useful for setting the width of text elements. This is because the width of a text element can be based on the number of characters it contains. For example, the following code sets the width of a paragraph to 40 times the width of the character '0' of the font being used:
p {
  width: 40ch;
}

2. Setting the width of containers that hold text

CH units can also be used to set the width of containers that hold text. This is useful when you want the container to be as wide as the text it contains. For example, the following code sets the width of a div to 30 times the width of the character '0' of the font being used:
div {
  width: 30ch;
}

3. Setting the font size

CH units can be used to set the font size of text elements. This is useful when you want the font size to be relative to the width of the characters in the font. For example, the following code sets the font size of a paragraph to 2.5 times the width of the character '0' of the font being used:
p {
  font-size: 2.5ch;
}

4. Setting the line-height

CH units can also be used to set the line-height of text elements. This is useful when you want the line-height to be relative to the width of the characters in the font. For example, the following code sets the line-height of a paragraph to 1.5 times the width of the character '0' of the font being used:
p {
  line-height: 1.5ch;
}

5. Creating responsive layouts

CH units can be used to create responsive layouts that adjust based on the font size. This is because the width of the characters in the font will change as the font size changes. For example, the following code sets the width of a paragraph to 20 times the width of the character '0' of the font being used:
p {
  width: 20ch;
}
As the font size of the paragraph changes, the width of the paragraph will adjust accordingly.

Sources

MDN Web Docs