Easy Responsive Video is a WordPress plugin that adapts oEmbed video to full width while maintaining aspect ratio.
Automatically adapt your embedded videos to the full width of their containers while maintaining the correct aspect ratio.
This is a simple filter that scans each embed in your posts, pages and custom post types, reads the width and height on the iframe and adds a style attribute including CSS width, height and aspect-ratio properties.
Currently supporting YouTube, Vimeo, WordPress/VideoPress and DailyMotion.
I'm the devloper for the film writer Vern and had been using the plugin Fluid Video Embeds for years. After noticing a large number of errors in the server logs I discovered it was no longer maintained. The other solutions I found wrapped the iframe in a div and used CSS tricks to scale and maintain aspect ratio, and many required changing the links to shortcodes. I wanted a simple solution that would work with both Classic editor URLs as well as modern embed Blocks. This is my solution.