PDF metadata, and what to do about it

Runs on your device. Nothing is uploaded.

Inspect hidden document properties, edit or remove the fields you know about, and trace the file’s structural history when the current values are not enough.

PDF Metadata ViewerInspect properties Edit PDF MetadataSet fields, one or many Remove PDF MetadataStrip hidden data, in batches

Which tool should I use?

Start with the viewer when you are not sure what is inside the file.

I want to know what is in the file: Read the properties, the XMP and the EXIF inside its images. View Metadata
I need revisions, objects or signature evidence: Trace xref history, orphaned data, signed byte coverage and visual differences. View Metadata
A field is wrong and I want it corrected: Set Title, Author, Subject, Keywords, Creator, Producer and dates. Edit Metadata
I am about to share this and want it clean: Strip the properties, the XMP, image EXIF, annotation authorship and attachments. Remove Metadata

Where a PDF keeps it

A PDF can carry descriptive metadata in its Document Information dictionary, an XMP stream, or both — plus structural detail such as version, page count, forms, fonts, image objects, signature fields and security settings.

Document Information

Title, Author, Subject and Keywords.
Creator and Producer — the authoring app, and the one that wrote the PDF.
Creation and modification dates.

XMP and identifiers

XML metadata that often repeats the fields above, and can disagree with them.
Document and instance IDs, language, metadata timestamps.
PDF/A declarations and application-defined properties.

Metadata is useful evidence about a file, but most of these fields are editable. Treat Author, Creator, Producer and timestamps as context rather than proof of authorship or chronology.

Understand what the fields actually mean

Practical explanations based on the PDF specification and the same structures these tools read in the browser.

What is PDF metadata?The fields a PDF can carry — title, author, dates, the software that made it — and which of them travel with a file you share.Read Creator vs ProducerTwo fields that look interchangeable and are not. Creator names the program you wrote in; Producer names the one that wrote the PDF.Read Can a PDF reveal its author?What a document actually gives away about who made it, why it is weaker evidence than people assume, and how to strip it before sharing.Read A free alternative to Adobe Acrobat SanitizeWhat a browser tool measurably removes, set against what Adobe documents Sanitize Document as doing — and the four things Acrobat does that it does not attempt.Read What’s hidden inside a PDF?Metadata, earlier saves and the other information a page preview cannot show.Read

Why local processing matters

Not a policy we promise to follow — a consequence of where the work happens.

How a server-based tool works

The document is transmitted to a provider before anything can be read.
Privacy then depends on that provider’s transmission, retention and security practice.
You are trusting a policy you cannot inspect.

How this works

The PDF is opened and rewritten inside the browser tab.
No upload is required for inspecting, editing or cleaning.
Inspect, Edit and Clean share one loaded file, so nothing is read twice.

PDF metadata questions

Does Lyonite upload my PDF for metadata processing?

No. These metadata workflows process the PDF locally in your browser instead of uploading the document to Lyonite for processing.

Should I view metadata before editing or removing it?

Usually, yes. Inspecting first shows what information is present and helps you decide whether to keep, change, or remove specific fields.

Does removing metadata make a PDF anonymous?

No. Metadata cleaning is one privacy step. Visible text, annotations, form values, attachments, embedded files, images, and other content can still identify a person or organization.

Opening tool…