PDF Metadata Editor

Introduction

When you email a legal document, share a PDF portfolio, or publish a report on a website, the file's hidden metadata travels with it. The Author field might contain your personal name or your company's internal naming conventions. The Creator field might reveal which software version you're using — something you'd rather not share with clients or competitors. The Keywords field might have been accidentally populated with internal project tags.

This PDF Metadata Editor lets you view all the current metadata properties in any PDF and then freely edit or clear them — all without uploading your file anywhere. Change the author name, update the title, clear the subject, or wipe all fields blank in a few clicks. The modified PDF downloads immediately.

Technical & Concept Breakdown

PDF metadata is stored in the Document Information Dictionary — a simple key-value structure at the end of the PDF's cross-reference table. The tool opens this dictionary using pdf-lib, displays the current values, and lets you overwrite each field.

The edit process works like this:

1. PDFDocument.load(buffer) — reads the full PDF into memory
2. pdfDoc.setTitle('New Title') — overwrites the /Title key in the Info dictionary
3. pdfDoc.setAuthor('New Author') — same for /Author
4. pdfDoc.setSubject(...), pdfDoc.setKeywords([...]), pdfDoc.setCreator(...), pdfDoc.setProducer(...) — remaining editable fields
5. pdfDoc.save() — serializes the modified PDF back to binary

To clear a field, you simply set it to an empty string. pdf-lib writes an empty string value for that key, which PDF readers display as "none" or leave blank.

What you can and can't edit: You can edit the "soft" metadata fields: Title, Author, Subject, Keywords, Creator. The CreationDate is technically editable but is set automatically on save. ModDate is always automatically updated to the current timestamp by pdf-lib on save — this is by design in the PDF specification.

Real-World Use Cases

Freelancers & Agencies: Before delivering a client project as a PDF, clear out internal Author tags that might reveal your employee's name or an internal project code.

Academics: Update or correct the Author field on research papers before submission to conferences or journals.

Publishers: Standardize the metadata across a batch of PDFs — ensuring consistent Author, Creator, and Keyword formatting across an entire publication series.

**Legal...