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Use CSS Instead of JS to Improve Website Performance
Improve Website Performance Using CSS, In some cases, Javascript is used instead of CSS for design implementation when CSS could provide the same result.
In order to reduce blocking time (TBT) in design and implementation, we will always look at CSS as an alternative to Javascript for certain design elements.
In order to reduce blocking time (TBT) in design and implementation, we will always look at CSS as an alternative to Javascript for certain design elements.
Many things can now be done with CSS rather than more complex Javascript thanks to advanced CSS.
TBT is the major reason for a lower Google page speed score on mobile devices.
The content below derives from our experience executing over 50+ speed optimization projects on Shopify websites. We have tried explaining how to load CSS instead of js for improving the site speed and solutions to minimize the impact on site speed.
Using CSS instead of javascript can help improve the performance of a website in several ways
- It’s better to use CSS instead of Javascript because Lesser Javascript means lesser TBT.
- CSS is generally faster to parse and executes than Javascript, so replacing JavaScript animations with CSS animations can improve the overall performance of the page.
- CSS can be used to apply styles and layout to a page, which means that the browser doesn’t have to recalculate the layout every time the page is updated. This can improve the perceived performance of the page.
- When using JS, the layout will be rerendered, which is not the case when using CSS.
Example
- Image Slider
- CSS animations are responsible for the menu on mouse hover
To summarize, using CSS instead of JavaScript can improve the performance of a website in several ways. CSS is faster to execute than JavaScript, and it can be used to apply styles and layouts to a page without requiring the browser to recalculate the layout.
