Diff Checker is a free online developer tool to compare text to find the differences between two text documents with syntax highlighting. Supports over 170 programming languages, such as C#, C/C++, CSS, Go, HTML, Java, JavaScript, JSON, PHP, Python, Ruby, XML, and more. The differences are highlighted by line.
This tool is designed to work in fullwidth on desktop by default. You can close the sidebar to expand the width a little more.