Compare files and folders

A short tech tip on how to compare files and folders using diff and merge software such as Meld. The basic Meld usage and features.

Sometimes, you want to compare files in two directories find the difference.

For example, when you update software on your site, would be good to know which files updated and how the changes may affect your installation. Or maybe you’ve (or your developer) changed some files on your site and forget where the changes were made.

Obviously, you won’t check each file line by line. You certainly need a tool, which can find all differences and give you visual report.

One of such tools is the Meld. It’s free, open source and available for Linux, Windows and OS X users.

Meld helps you compare files and directories in two- and even three-way overview. You also can manage files under version control, such as Git or Subversion.

Meld welcome screen screenshot

Meld welcome screen


Example below shows how looks comparison of the ClassiPress versions 4.1.4 against version 4.1.5.

Compare directories screenshot

Compare directories

Here you can see two panes side by side with the different files trees:

  • Unchanged files skipped.
  • Changed files highlighted with a blue color.
  • New files highlighted with a yellow color.
  • There are diff maps next to the vertical scroll bars which gives you an idea on the overall scales of the changes in the folder.

Filters can help to hide files without differences, new or changed, so you can reduce the list of files in the comparison. Moreover, you can filter out files by mime types or by a name pattern.

Click on the changed file for detailed difference report.

Compare files pane screenshot

Compare files

  • New code block highlighted with a green color.
  • Changed blocks highlighted with a blue color.
  • The arrows allow applying changes from side to side. 
  • There also are diff maps to show where in the file changes appear.
  • Meld allows editing files likewise you use a regular file editor.

Compare files and directories with ease using diff tools such as the Meld.