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Choose one PDF up to 20 MiB and 500 pages, or create the safe two-page sample.
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Choose an action, then enter replacement text only when Replace is selected.
Use Clear when the author entry should be absent rather than blank-looking text.
The subject is descriptive metadata; it does not change visible page content.
Separate replacement terms with commas, semicolons, or line breaks.

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Optional technical metadata. Keep is neutral.
Optional technical metadata. Keep is neutral.
Example: 2026-08-25T09:30:00+08:00. Keep is neutral.
Example: 2026-08-25T01:30:00Z. Keep is neutral.
Verified local output
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Changed fields
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Pages preserved
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Output size
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SHA-256
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{{ pdfDownloaded ? 'Download started' : 'Download updated PDF' }}
FieldActionBeforeAfterOutcomeCopy
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CheckEvidenceStatusCopy
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PDF Page Manager Reorder or extract PDF pages and rotate or split them locally in your browser with typed ranges, page-flow checks, and a source-to-output manifest.
PDF Compressor Compress a PDF locally in your browser, compare structural and production estimates, and catch encryption or image-quality risks before download.
Exchangeable Image File Format (EXIF) Viewer & Editor Inspect EXIF metadata locally, flag location and device details, then export a stripped or selectively edited image with an auditable privacy score.
Image Metadata Stripper Strip hidden metadata from an image in your browser and create a clean JPEG, PNG, or WebP copy with a check for remaining privacy markers.

A PDF can carry descriptive information that never appears on a page. Titles, authors, subjects, keywords, creation dates, and the applications that produced the file help document systems catalogue and search it. They can also reveal names, software, and timestamps that were not meant to travel with a public copy.

PDF metadata has more than one home. The document information dictionary, often called Document Info, stores familiar properties such as Title, Author, and ModDate. A separate Extensible Metadata Platform (XMP) stream may repeat some of those properties and hold richer metadata. Changing one store does not automatically make the other agree.

Surface Typical Contents Important Boundary
Document Info Title, author, subject, keywords, creator, producer, creation date, and modification date. These are the standard properties edited here.
XMP stream XML-based metadata, including properties that may duplicate Document Info. The existing stream is preserved unchanged, so duplicated values may disagree after an edit.
Page content Visible text, images, drawings, and page instructions. Changing metadata does not redact visible content or hidden content elsewhere in the PDF.
Digital signatures Cryptographic evidence tied to the signed byte ranges and document state. Saving a modified PDF can invalidate or alter signature status even when page content is unchanged.

Use metadata edits for cataloguing, correction, and privacy cleanup only after deciding what should be kept. Clearing an author field removes that Document Info entry; replacing it writes a new value. Neither action proves that the same name is absent from XMP, attachments, annotations, form data, revision history, or visible pages.

A careful result therefore needs two checks: confirm the intended property changed, then verify that the document content and any metadata store deliberately left untouched still match the expected state.

How to Use This Tool:

Load one unlocked PDF, choose an explicit action for each property that needs attention, and review the saved file before treating it as the final copy.

  1. Select a Source PDF up to 20 MiB and 500 pages. Password-protected or encrypted files are not accepted.
  2. For title, author, subject, and keywords, leave Action on Keep, choose Replace and enter a value, or choose Clear to remove the entry.
  3. Open Advanced only when creator, producer, creation date, or modification date needs changing. Date replacements require an ISO 8601 timestamp with Z or an explicit UTC offset.
  4. Select Update PDF metadata. If the requested values already match the source or every action remains Keep, change the plan before trying again.
  5. Review the Metadata change ledger for each before-and-after value, then inspect PDF preservation checks for page count, page-content stream hashes, and XMP status.
  6. Download the updated PDF and open it in the viewer used by the recipient. Recheck properties and any existing signature status there.

Interpreting Results:

Changed fields counts values that differ after Keep, Replace, and Clear are resolved. A requested replacement that exactly matches the existing value is unchanged, and a plan with no effective change is stopped rather than saved as a misleading new file.

A preservation pass confirms that the page count and raw page-content streams match the inspected source after saving and reopening the output. It also confirms that an existing document-level XMP stream has the same bytes. These checks are narrower than full byte-for-byte equality because writing a PDF can change object layout and file structure.

An XMP result marked for review means the stream was deliberately preserved, not synchronized. If a viewer shows a different property than the change ledger, inspect both Document Info and XMP before deciding which value should be authoritative.

Technical Details:

Document Info is an optional PDF dictionary whose standard values are text strings or dates. Editing it is a rule-based document transformation: each known field receives exactly one action, the replacement value is normalized, and the resulting dictionary is written before the document is saved and reopened.

Rule Core:

Action Rule Outcome
KeepIgnore the typed replacement field and retain the inspected Document Info value.No requested change for that property.
ReplaceRequire non-empty text, normalize line endings and surrounding whitespace, then write the normalized value.The property is added or replaced when its value differs.
ClearDelete the corresponding key from the Document Info dictionary.The property is absent rather than stored as blank-looking text.

Keywords are split on commas, semicolons, or line breaks, trimmed, deduplicated in first-seen order, and stored as a space-separated keyword value. Date replacements must include a timezone; they are converted to Coordinated Universal Time (UTC) and saved with millisecond precision.

Transformation Core:

Stage Operation Evidence Kept
Inspect sourceOpen the PDF, read the eight standard Document Info fields, count pages, and fingerprint page-content streams and any document-level XMP stream.Source metadata, page count, content hash, and XMP hash.
Build edit planValidate one Keep, Replace, or Clear action for every field and reject plans with no effective change.Normalized actions and a complete before-and-after ledger.
Apply and saveWrite or delete only the selected Document Info keys, then serialize a new PDF.Updated Document Info values and output file bytes.
Reload and verifyOpen the saved file and compare page count, raw page-content stream hash, and XMP presence and hash with the source.A downloadable result is exposed only after every required comparison passes.
Boundary Accepted Value Failure Result
Source sizeUp to 20 MiBLarger files are not processed.
Page count1 to 500 pagesEmpty or oversized documents are rejected.
Property lengthUp to 2,000 characters after normalizationThe edit plan requires a shorter value.
Date formValid ISO 8601 date and time with Z or an explicit offsetThe replacement is rejected before saving.
Output sizeUp to 30 MiBAn oversized generated PDF is discarded.

The supported fields are Title, Author, Subject, Keywords, Creator, Producer, Creation date, and Modification date. Custom Document Info keys and XMP properties are outside the edit plan.

Privacy and Preservation Notes:

The selected PDF and generated output remain in the current browser session and are not uploaded by this tool. Local processing limits transmission risk, but the downloaded file still needs a metadata and content review before publication.

  • XMP is preserved unchanged. It may retain a title, author, date, identifier, or custom property that differs from the edited Document Info value.
  • Page-content stream matching does not audit annotations, attachments, form values, bookmarks, embedded files, custom metadata, or every other PDF object.
  • Saving changes can invalidate digital signatures or alter certification status. Verify signed documents in a signature-aware PDF viewer.
  • Metadata removal is not redaction. Inspect visible pages and other document structures when sensitive information must be removed.

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