As a front-end developer, you are constantly looking for ways to work more efficiently and improve the visitor's user experience. One way to achieve this is by using CSS logical properties and values. These properties not only provide a more intuitive way to style elements, they also contribute to better code formatting and also add value to the user.

Flexibility in text orientation

One of the biggest advantages of CSS logical properties is that they adapt to different writing and reading directions. Instead of using specific properties for left-to-right (LTR) and right-to-left (RTL) languages, logical axes are now automatically adjusted. Content with "text-align: start" will align left in an LTR language, and with the same code, this text will align right in an RTL language.

Instead of relying on physical directions, the logic automatically adapts to the user's context. Regardless of language or text direction, this ensures a consistent appearance and clear, easy-to-maintain code.

What are "logical properties and values"?

Traditionally, we define the dimensions of elements on a Web site with physical properties. For example, they have a height and width or we can position elements from top to bottom and left to right. But margins, padding, border-radius and alignment are also determined with physical properties. With CSS Logical properties and values, we link the orientation of elements to two logical axes.


Block & inline

The axis of reading direction is the "inline" axis and on it is the "block" axis. Each axis has a "start" and an "end" point.

For example, "width" now becomes "inline-size", "height" becomes "block-size",and "padding-top" becomes "padding-block-start".

Better support for international websites

Websites are evolving and increasingly targeting a global audience. With a growing demand for multilingual and international websites, the use of "logical properties and values" is essential. By adjusting the "dir" attribute, the layout will adapt to the reading direction. Additional adjustments after translation to an RTL language will remain limited.

<html dir=”ltr”>
<html dir=”rtl”>

The "dir" attribute informs browsers that content should be displayed in either LTR or RTL mode. This attribute was also previously used to adjust the specific styling for RTL for each CSS class.

Example of how it used to be:

.quote {
  margin-left: 1rem; /* LTR */

[dir="rtl"] .quote {
  margin-left: 0;
  margin-right 1rem; /* RTL*/

With "logical properties and values," this can now be done in one line of code:

.quote {
  margin-inline-start: 1rem;

More examples of logical CSS properties

/* height: 1rem; */
block-size: 1rem; 

/* max-width: 1rem; */
max-inline-size: 1rem;

/* text-align: right; */
text-align: end;

/* right: 1rem; */
inset-inline-end: 1rem;

/* border-bottom-width: 1rem; */
border-block-end-width: 1rem;

/* padding-left: 1rem; */
padding-inline-start: 1rem;

/* border-top-right-radius: 1rem; */
border-start-end-radius: 1rem;

The layout now adapts to the reading direction

Layout from left to right:


Right to left lay-out:

Tips for writing good RTL CSS

  • Use logical properties from the start of a project and use them everywhere. If there are still some physical CSS declarations in the project, it will give an undesirable effect in an RTL environment. Therefore, test adequately.
  • When changing the reading direction, only CSS properties related to layout and text flow will get a different visual result. Icons or shadows, without additional code, will simply retain their display.
  • Images and icons may need to be adjusted in RTL layouts to maintain visual balance and context. The :dir pseudo class also allows us to adjust the direction for properties related to paint.
:where(.breadcrumbs, .pager):dir(ltr) svg {
  scale: -1 1;
  • Layouts formatted with flexbox and grid also adapt to the reading direction, which flexbox and grid also use the logical "inline" and "block" axes.


Using "logical properties and values" offers numerous benefits to developers, ranging from flexibility and ease of maintenance to improved international support and future-proofing. By embracing this approach, you can work more efficiently and deliver high-quality Web experiences to a global audience.