A PDF structure validator checks a PDF file's internal structure for validity — the PDF header signature, version number, cross-reference table, and EOF marker. Use it to detect corrupted, truncated, or improperly generated PDFs before distributing them. All validation runs in your browser using the File API — no upload needed.
Drop a PDF file here, or click to browse
Accepts .pdf files. File is read locally — never uploaded.
Structural Checks
Extracted Metadata
This validates PDF structure (header, EOF, xref, trailer), not content. For full PDF/A or PDF/UA compliance use specialized tools.
How to Validate a PDF File
A PDF validator helps you confirm a PDF file is structurally sound before distribution. Corrupted PDFs can fail to open in Acrobat Reader, display blank pages, or lose content — catching these issues early saves support headaches.
Step 1: Upload Your PDF
Drag and drop your PDF into the upload area, or click to browse for the file. The file is read entirely in your browser using the JavaScript File API — it is never sent to any server, making this safe for confidential documents.
Step 2: Review Structural Checks
The validator checks six structural elements: the %PDF-
header (confirms it's actually a PDF), PDF version (must be 1.0–2.0), %%EOF
marker (confirms file is complete), cross-reference table (the internal index), trailer dictionary
(required for PDF parsing), and basic file integrity (non-zero size).
Step 3: Check Extracted Metadata
If the PDF is valid, the tool extracts available metadata: title, author, creator application, producer (the PDF library used), and creation/modification dates. This is useful for confirming document provenance or checking what application generated the PDF.
Understanding PDF Structure
A well-formed PDF file starts with %PDF-1.x
(or 2.0), contains object definitions, a cross-reference table for random access, a trailer dictionary,
and ends with %%EOF. Missing any of these
elements indicates file truncation or corruption. Linearized (web-optimized) PDFs have a slightly different
structure but still include all required markers.
FAQ
Is this PDF validator free?
Yes, completely free with no account required. Upload or drag-and-drop a PDF file to validate its structure instantly. All processing runs in your browser — the file is never uploaded to any server.
Is my PDF file safe and private?
Yes. The PDF is read locally in your browser using the File API. The file contents never leave your device and are not stored, logged, or transmitted anywhere.
What does the PDF structure validator check?
It checks: valid PDF header (%PDF- signature), PDF version (1.0–2.0), EOF marker (%%EOF), cross-reference table (xref), trailer dictionary, and file size. It also extracts available metadata like title, author, creator, and creation date.
Can this tool check PDF/A or PDF/UA compliance?
This tool validates basic PDF structural integrity — the header, EOF marker, xref table, and trailer. Full PDF/A (archival) or PDF/UA (accessibility) compliance checking requires specialized tools that parse the entire document structure and embedded metadata schemas.
How do I know if my PDF is corrupted?
A corrupted PDF will fail one or more structural checks: missing %PDF- header, no %%EOF marker, or an invalid/missing xref table. These indicate the file was truncated or improperly written. If the PDF opens fine in Acrobat but fails here, it may use a non-standard structure.
What is the xref table in a PDF?
The cross-reference (xref) table is an index of all objects in the PDF file, mapping object numbers to byte offsets. It allows PDF readers to randomly access objects without reading the entire file. A missing or corrupted xref table forces readers to rebuild it, which can fail on damaged files.