Provenance
Where image metadata gets stripped: WordPress, CDNs and uploads
Quick answer
Metadata is lost at every step that re-encodes a file. WordPress generates resized copies and, depending on the image library, may drop metadata from them; optimisation plugins and CDNs often strip it deliberately to save bytes; and most social networks re-encode uploads. If provenance matters, serve the original file for the og:image, turn off stripping for it, and test the result.
On this page
The journey of an image
Provenance data lives inside the image file: IPTC fields for captions, credits and the digital source type, EXIF for camera details, and C2PA manifests for signed history. Any tool that decodes the pixels and writes a new file decides afresh what to keep. Many keep nothing, because metadata is weight and most sites never read it.
Step by step, where it goes missing
| Step | What usually happens | What you can do |
|---|---|---|
| Export from an editor | Settings may drop metadata to reduce size | Enable keeping metadata and credentials on export |
| WordPress upload | Resized copies are regenerated; the image_strip_meta filter controls stripping in some setups | Check the filter and your image library behaviour |
| Optimisation plugin | Often strips metadata by default | Exclude featured and og images, or keep IPTC |
| CDN image resizing | Frequently strips unless told otherwise | Use a preserve-metadata option where offered |
| Social network upload | Re-encodes and usually removes most fields | Nothing on your side; rely on page captions |
The WordPress developer reference documents the image_strip_meta filter for image editors that support it, which is the switch to look at when resized copies lose their fields. Check it on a staging copy rather than assuming, because behaviour depends on the image library your host provides.
A practical setup for provenance
- Keep the original upload intact and point
og:imageat a size that is generated with metadata kept, or at the original when it is already 1200 by 630. - Exclude featured images from aggressive optimisation, or configure the optimiser to preserve IPTC and C2PA data.
- After publishing, download the image from your own page and inspect it. If the fields are gone there, no network will ever see them.
- Keep a caption on the page regardless, as the guide to labelling AI images in link previews recommends.
The IPTC Photo Metadata Standard lists the fields and where they are stored, and the C2PA specification describes how manifests are embedded. Both assume the file is left alone; the practical work is making sure your own stack does that. For the reader's side of the same problem, see checking Content Credentials before you share. The rest of the provenance section covers the authorship signals that do not depend on files at all.
Sources
- WordPress developer reference: the image_strip_meta filter
- IPTC Photo Metadata Standard 2025.1
- C2PA Content Credentials technical specification 2.1
Questions
Does WordPress remove image metadata?
It can, depending on the image library and the image_strip_meta filter. Resized copies are the usual place fields go missing, so test your own install.
Do CDNs strip EXIF and IPTC data?
Many image resizing services strip metadata by default to save bytes. Look for an option to preserve it for the images that need provenance.
Do social networks keep image metadata?
Most re-encode uploads and remove most fields. Some read provenance data on upload before stripping it, which is how certain labels are applied.
Should I keep GPS data in published photos?
Usually not. Keep credit, caption and source type fields, and drop location for privacy.
Hannah Voss, Editor. Checks every guide against a working WordPress install and the networks' current documentation. Last reviewed September 2026.
Related reading
- Checking Content Credentials before you share an imageHow to check an image's Content Credentials before you share or publish it: what a C2PA manifest shows, what a missing one means, and what to record.3 min read
- Labelling AI-generated images in link previewsHow to label an AI-generated og:image honestly: captions, alt text, digital source type metadata and what networks show when the card is shared.3 min read
- Content Credentials on shared images: what survives a shareWhat C2PA Content Credentials are, why WordPress image sizes and social uploads often strip them, and how to keep provenance on the images you share.4 min read
- Facebook showing the wrong image or share textFix Facebook showing the wrong image or text when you share a WordPress post: duplicate tags, small images, cache, blocked crawlers, and the Sharing Debugger.3 min read