What Is a File Drag & Drop Test?
This tool uses the browser's standard HTML5 Drag and Drop API to let you drop a file directly onto the page and see its real metadata - exact filename, size in bytes, reported MIME type, and last modified timestamp - all read locally from the file object your browser provides. The file itself is never uploaded, read into memory beyond this basic metadata, or transmitted anywhere.
How to Use the File Drag & Drop Test
- Drag any file from your desktop or file manager over the box above.
- Release it to drop the file, or click the box to browse and select one instead.
- Review the real file details that appear: name, size, type, and last modified date.
- Try a different file to see the metadata update instantly.
How It Works
This tool listens for the standard dragover, dragleave, and drop
events on the drop zone, along with a regular file input as a click-to-browse alternative for
non-drag-and-drop use. When a file is dropped or selected, the browser provides a genuine
File object with real properties - name, size, type, and
lastModified - read directly from that object and displayed as-is, without any upload or
further file content access.
Understanding Your Results
- File details display correctly and instantly - your browser's Drag and Drop API is functioning normally.
- File type shows "Unknown" - some file types, particularly ones your operating system doesn't have a registered MIME type for, may not report a type; this is a limitation of how the file system labels the file, not a fault in this test.
- Drop doesn't register at all - confirm you're dropping directly onto the highlighted zone; dropping outside its boundaries won't trigger the drop event.
- Last Modified date looks unexpected - reflects your operating system's own file metadata, which can sometimes change due to file copying, syncing services, or system operations unrelated to actually editing the file's content.
Browser Limitations
This test only reads the metadata your browser's File object exposes - it does not, and
cannot, read the file's actual content unless you specifically build functionality to do so, which this
test intentionally doesn't include, keeping the check purely informational and privacy-respecting. Reported
MIME type accuracy depends on your operating system's own file type registration, not on this tool.
Common Mistakes to Avoid
- Dropping multiple files at once - this test reads only the first file if multiple are dropped together; test one file at a time for clarity.
- Expecting file content preview - this tool intentionally shows only metadata, not the file's actual contents.
- Assuming a missing file type means a corrupted file - an unrecognized type more often reflects how your operating system labels that specific file extension, not file corruption.
Frequently Asked Questions
Is my file actually uploaded anywhere during this test?
No. Only the file's basic metadata (name, size, type, and modified date) is read locally in your browser - the file's actual content is never uploaded, read, or transmitted.
Why does the file type sometimes show "Unknown"?
Your operating system determines what MIME type gets reported for a given file extension; some file types, especially uncommon or custom ones, may not have a registered type recognized by the browser.
Can I test dropping a folder instead of a file?
This test is built specifically for single file drops; folder drag-and-drop behaves differently across browsers and isn't covered by this particular tool.
Why does drag-and-drop work but clicking to browse doesn't, or vice versa?
Both methods are implemented independently here; if one isn't working, try refreshing the page, since this can occasionally indicate a temporary browser state issue rather than a fundamental incompatibility.
Does this work on mobile devices?
The click-to-browse method works well on mobile, though true drag-and-drop from a device's file manager onto a webpage isn't consistently supported across all mobile browsers the way it is on desktop.
Conclusion
Whether you're confirming your browser's drag-and-drop functionality or just want a quick, private look at a file's real metadata without uploading it anywhere, this gives you exactly that. For a related check of clipboard functionality, see the Clipboard Test.