XMP Metadata
Also known as: xmp sidecar, adobe xmp, xmp metadata
XMP (Extensible Metadata Platform) is an Adobe-created, XML-based standard for embedding metadata such as edits, ratings, keywords, and copyright into images, PDFs, and video, either inside the file or in a separate .xmp sidecar file. It adds a small amount to file size.
- Adobe's XML-based metadata standard (ISO 16684) for images, PDFs, RAW, and video.
- Can be embedded in the file or stored as a separate .xmp sidecar beside RAW originals.
- May contain GPS, device, and copyright data worth stripping before sharing.
What XMP metadata is
XMP, the Extensible Metadata Platform, is a standard Adobe introduced in 2001 and later published as ISO 16684. It stores metadata as XML wrapped in an RDF structure, making it more flexible and extensible than the older EXIF and IPTC schemes, which it can also mirror and carry alongside.
XMP can record edit history and develop settings (in RAW workflows and Adobe Camera Raw / Lightroom), star ratings, keywords, captions, GPS location, copyright and licensing, and authorship. It is supported across JPEG, TIFF, PNG, PDF, DNG, and many video and document formats.
Embedded vs. sidecar files
XMP can live two ways. It is often embedded directly inside the image or document. For formats that cannot or should not be modified, especially proprietary camera RAW files, editors instead write a separate .xmp sidecar file that sits next to the original and shares its base filename.
Sidecars are why a photo library can contain many small companion files: each edited RAW may have a matching .xmp holding its adjustments. These are easy to overlook, and orphaned sidecars (whose original image was deleted or moved) become clutter that adds file count without serving any purpose.
Why it matters for storage and privacy
Embedded XMP adds only a small amount to a file's size, but like EXIF metadata it can carry sensitive details such as GPS coordinates, device info, and your name in the copyright fields. Stripping metadata before sharing protects privacy and trims a little weight.
On a phone, the bigger storage angle is photo and video volume rather than the metadata itself. Cleanor helps by finding duplicate and similar photos so you can clear real space, while metadata-aware editing or metadata removal keeps location and identity data out of images you post.