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PDF Keywords for Searchable Document Metadata

No PDF selectedList, add, or remove PDF metadata keywords.
KeywordsPDFs are shared across all tools.

What are PDF keywords, and how do you edit them?

PDF keywords are metadata terms stored with a document to describe its subject or help a document system classify it. Upload a PDF to inspect its current keyword list, then add, replace or remove terms and download the updated file. Editing these tags does not alter the visible page text, and keywords alone do not guarantee that a PDF will rank in web search.

Cost: Free to use. File size and usage limits apply.

How to list, add or remove PDF keywords

  1. Upload one PDF

    Click Upload PDF or drop a file onto the preview area. Files up to 200 MB are accepted. You can also pick a PDF from Uploads, including a result you just created with another PDF tool.

  2. Check what is already there

    List keywords is the default Action. Click Apply keywords to read the current keywords without changing the file. They appear one per line; Copy puts the list on your clipboard and Download result saves it as a text file.

  3. Choose Add or Remove

    Switch Action to Add keywords or Remove keywords. The Keywords box appears below it.

  4. Type the keywords

    Separate them with commas or put each one on its own line. For removal, copy the exact spelling from the list you created in step 2.

  5. Apply and download

    Click Apply keywords. The preview switches to the updated PDF and Download result saves it. To double-check, select that result in Uploads and run List keywords on it.

Settings explained

The tool has two controls. Keywords only appears when you add or remove.

Action: List keywords
Reads the keywords and returns them as plain text. The PDF is not changed and no new PDF is created. Treat the result as a set of tags; their order is not guaranteed.
Action: Add keywords
Adds the entered keywords to the ones already in the file. Existing keywords stay. A keyword that is already present with exactly the same spelling is not added a second time.
Action: Remove keywords
Deletes only the keywords you enter and keeps all others. Matching is exact and case-sensitive: Invoice does not remove invoice. If none of the entered keywords is found, nothing is removed and you get an error message instead of a new file.
Keywords
Starts empty. Enter at least one keyword for Add or Remove, separated by commas or line breaks. Spaces inside a keyword are kept, so annual report stays one keyword; spaces at the start and end are trimmed. Unicode text such as Größe or 日本語 is supported. Commas and semicolons separate keywords in stored PDF metadata, so keep them out of a tag that should remain one phrase.

Where PDF keywords are stored

A PDF has a single Keywords entry in its document information, next to title, author and subject. It is one text string, not a list, which is why programs show it with commas or semicolons in between. Many PDFs also carry XMP metadata, an embedded XML block that can hold its own copy of the keywords.

This tool reads both places, so List keywords also shows keywords that exist only in the XMP block. When you add or remove keywords, the complete list is written back to the Keywords entry, separated by ; , and keywords from the XMP block are moved into it. You end up with one keyword list that PDF readers show in their document properties.

Pages look exactly as before: nothing is re-rendered and images are not re-encoded. Title, author and subject stay as they are, and the modification date is set to the time of processing. Because the file is saved again, its size can change.

Use keywords in document management software, archives or desktop search that read this metadata. Keep a consistent vocabulary, such as project codes or client names, so files can be classified under the same terms. For a PDF you publish, also give it a descriptive title with PDF Properties and useful, readable page content. Changing keywords alone does not establish that a search engine will index or rank the file.

Formats and limits

Input format
PDF. Files that need a password to open must be unlocked first with Unlock PDF.
Output of List keywords
Plain text, one keyword per line, to copy or download as a .txt file
Output of Add and Remove
PDF with the same pages and the updated keyword list
Maximum file size
200 MB
Files per job
1 PDF
Processing
On our servers with the pdfcpu PDF library. No external or AI service is involved. A job can run for up to 15 minutes.
Watermark
None
Storage
Uploads and results are deleted automatically after 48 hours for guests and after 30 days for free accounts. Paid plans can keep files longer.

Frequently asked questions

Why can't Remove keywords find a keyword that is in the list?

Removal needs the exact spelling, including upper and lower case and any spaces inside the keyword. Run List keywords, copy the entry and paste it into the Keywords box.

How do I replace all keywords with a new set?

Use two passes. Run Remove keywords with every keyword from the current list, then select the result in Uploads and run Add keywords with the new set. Any keyword you leave out of the removal stays, so list the final file once more.

Do PDF keywords help a PDF rank in search engines?

This tool updates the PDF's metadata and makes no indexing or ranking promise. Keywords can help archives and document systems that read this field. They do not replace useful page content or a descriptive document title.

Does editing keywords change the pages or reduce quality?

No. Pages, text and images are not re-rendered or re-encoded. The metadata is updated and the file is saved again, so the file size can change.

Where else can I see a PDF's metadata?

PDF Info shows the keywords together with title, author, page count and PDF version. Most PDF readers also list them in their document properties.