Make Filename Lowercase
View on WordPress.orgScores higher than 8% of indexed plugins
About
Sets uploaded media filename to lowercase.
What It Does
Make Filename Lowercase automatically converts uploaded media filenames to lowercase as they are added to the WordPress Media Library. It hooks into the upload process and applies PHP's strtolower function to the filename before it is saved. The plugin does not rename existing files already in your library, only new uploads from the point of activation onward.
Who It's For
This plugin is best for sites where consistent lowercase filenames matter for organization, cross-platform compatibility, or development workflows that assume case-insensitive paths. It suits media-heavy blogs, multi-author publishing platforms, and digital asset libraries where contributors may upload files with mixed casing from different operating systems.
Who Should Skip It
If you already enforce a lowercase naming policy through team conventions or a custom upload handler, this plugin adds no value. Sites with an existing media library of mixed-case filenames will also not benefit, since the plugin only affects new uploads.
The Bottom Line
Make Filename Lowercase does one narrow thing and appears to do it well, earning a 96 user rating on a small sample. The overall quality score of 62.57 is held back by limited adoption and no support track record, but for users who need this specific behaviour it is a lightweight solution. The lack of an existing-file renaming option and unspecified PHP requirement are the main caveats to weigh before installing.
Related Plugins
Pick Safe SVG if your concern is sanitizing SVG uploads rather than normalizing filename casing, as it addresses a completely different media security gap.
Choose FileBird when you need to organize thousands of existing media files into folders rather than simply lowercasing new uploads.
Opt for Media Library Assistant if you want broad control over metadata, taxonomies, and bulk editing of your existing media library.
Select Media Cleaner when your priority is identifying unused files and reclaiming server space, not standardizing filename format.
Pick Default Featured Image if you need to auto-assign fallback featured images to posts, which is unrelated to filename handling.