What this tool does
PDF document properties (metadata) live inside the file: title, author, subject and keywords. They show up in the reader's properties panel and are the first thing search engines and reference managers (Zotero, EndNote) read — which is why "30 downloaded papers all have garbled titles" happens.
This tool rewrites those fields exactly as entered; blank means cleared. Pages, layout and annotations are untouched. Typical uses: giving a merged PDF a proper title, cleaning device names out of exported documents, or completing author info for archived papers. Everything runs in your browser.
How to use
- Fill in the fields Four independent fields: title, author, subject and keywords. Keywords accept commas/semicolons (both ASCII and full-width) and are split into a list automatically.
- Blank means cleared Only changing the title? Leaving the author blank clears it. This is intentional WYSIWYG semantics — no stale fields left behind.
- Download and verify After downloading, verify in any reader's document properties; page count and content are identical to the original.
FAQ
Does editing metadata affect page content?
No. Only the properties dictionary is rewritten; pages, images, fonts, annotations and bookmarks stay untouched, page count unchanged.
Why do search engines still show the old title?
Crawlers re-fetch online PDFs and update indexes over time; many sites display HTML page titles instead of PDF metadata anyway. Confirm the right file was updated and wait for reindexing.
Can I batch-edit multiple PDFs?
One file at a time (each has different metadata). For batches, use scripts or merge first and set once.
What about encrypted PDFs?
No. Files with an /Encrypt marker are intercepted; decrypt and save in the original environment first.
Will the file size change?
Slightly, due to re-serialization; content is unaffected. For maximum compression use the PDF compressor.
Is my file uploaded?
No. Editing runs in a browser Worker; the file never leaves your device.
Limits
Only four Info/XMP fields are edited (title / author / subject / keywords); Creator, Producer and others stay as-is.
Blank fields are cleared (written as empty values), not preserved.
Encrypted PDFs are rejected; up to 100MB per file.