Are my files uploaded online to check the PDF version number?

No. Our tool processes files 100% client-side within your local web browser. Your PDF documents are never uploaded to an external server or stored online, keeping your files completely secure on your device.

Do I need to sign up or create an profile to view a PDF's specification metadata?

No registration or account configuration is required. With no login required and zero data storage, you can instantly check specifications for unlimited documents completely free of charge.

Why does a document have different header and catalog PDF versions?

When a PDF file is updated or saved by modern editor software, the system often leaves the original version indicator in the file header (%PDF-1.x) unchanged and registers the newer, upgraded specification version inside the document Catalog dictionary. Our utility checks both locations to give you the true, functional version.

Can this utility detect if a PDF file is encrypted or password protected?

Yes. Alongside the core specification version (such as PDF 1.4 through ISO PDF 2.0), our local inspector script scans the structural dictionary to extract page counts, file size metrics, metadata records, and overall file encryption status.

PDF Version Checker (Free& No Login)

Free PDF Version Checker – Check PDF Version 1.4, 1.7, 2.0 Online | ThinkForU

Upload PDF to Check Version

Drop your PDF here

or click to select a file from your device

Your PDF never leaves your device · 100% private · No signup

—

PDF Version

—

Pages

—

File Size

—

Encrypted

Header Version
—
From the %PDF-x.y file header — the original creation version

Catalog Version

—

From the Document Catalog /Version entry — overrides header if present

—

Features Supported at This Version

PDF Version History

100% Private

PDF never uploaded to any server
Version read from raw file bytes in browser memory
No signup · No limits · 100% free

Zero Data Storage Policy →

Free PDF Utilities Suite

Free & No Login Required | Zero Data Storage

📁

PDF Merger

Combine multiple PDF documents into a single file easily.

🖼️

Image to PDF Converter

Convert your photos and pictures into high-quality PDF files.

📸

PDF to Image Converter

Extract pictures and convert PDF pages into image formats.

💎

PNG to PDF Converter

Convert transparent PNG graphics into clean PDF layouts.

📝

PDF to Text Extractor

Extract text scripts directly from your PDF files online.

🖼️

JPG to PDF Converter

Batch convert JPG photographs into single PDF packages.

✂️

Split PDF Online

Separate and extract individual page sets from a large PDF.

🔢

Add PDF Page Numbers

Insert custom dynamic pagination numbers to your PDF pages.

🛡️

Add PDF Watermark

Protect documents by stamping secure watermarks onto your PDF.

🌐

HTML to PDF Converter

Render complete web pages or raw HTML files straight to PDF.

🕵️

PDF Metadata Remover

Wipe hidden author records, titles, and tags from any PDF.

🔤

Text to PDF Converter

Convert raw notepad text scripts or strings into clean PDF layout.

📉

PDF Compressor

Reduce overall file sizes while keeping clean layout PDF views.

🖼️

PDF to JPG Converter

Transform individual file layouts into high-res JPG PDF frames.

🔄

Rotate PDF Online

Flip upside-down pages or sideways views within your PDF.

👁️

PDF Viewer Online

Read and inspect structured pages inside a 100% private PDF viewer.

🍏

HEIC to PDF Converter

Convert Apple HEIC photos directly into standard ready-to-print PDF.

🔚

PDF Font Finder

Identify and inspect precise typography types used inside any PDF.

📊

PDF Sentence Counter

Analyze metric counts and fetch true sentence counts in a PDF file.

📊

PDF Table Extractor

Pull structured table information or datasheet grids from your PDF.

📐

PDF to SVG Converter

Convert layouts into scalable vector graphics from high-res PDF.

🔍

PDF Image DPI Checker

Check resolution densities and pixel metrics inside embedded PDF elements.

⏱️

PDF Reading Time Estimator

Estimate total read length requirements across document text inside PDF.

🔤

PDF Character Counter

Run precise metrics tracking space allocations and letters in a PDF.

🔓

PDF Permission Checker

Verify printing, content modification, and copying access within a PDF.

🔒

PDF Encryption Checker

Inspect security cipher algorithms and raw restriction locks on a PDF.

Free PDF Version Checker — Check Any PDF Version (1.0 to 2.0) Online

PDF version matters more than most people realise. Version determines which features your document supports, which software can open it correctly, and whether it will pass compliance checks for archiving, printing, or legal submission. This tool reads both the file header version (%PDF-x.y) and the Document Catalog version (which can override the header) — plus encryption status, page count, metadata, and a full feature compatibility matrix. All processing happens in your browser — your file never leaves your device.

PDF Version Comparison Table

Version	Year	ISO Standard	Min. Acrobat	Key Features Added
PDF 1.0	1993	Adobe only	Acrobat 1	Basic text, images, vector graphics, hyperlinks
PDF 1.1	1994	Adobe only	Acrobat 2	Password security, external links, device colour spaces
PDF 1.2	1996	Adobe only	Acrobat 3	Interactive forms, halftones, better colour support
PDF 1.3	1999	Adobe only	Acrobat 4	Digital signatures, embedded files, smooth shading
PDF 1.4	2001	Adobe only	Acrobat 5	Transparency model, Tagged PDF, 128-bit RC4 encryption, PDF/A-1 base
PDF 1.5	2003	Adobe only	Acrobat 6	Object streams, JPEG 2000, Layers (OCG), cross-reference streams
PDF 1.6	2004	Adobe only	Acrobat 7	AES 128-bit encryption, OpenType fonts, 3D (U3D), collections
PDF 1.7	2006	ISO 32000-1 (2008)	Acrobat 8	AES 256-bit encryption, 3D (PRC), rich media, XFA forms, PDF/A-2 base
PDF 2.0	2017	ISO 32000-2	Acrobat DC	AES-GCM encryption, improved metadata, new annotation types, PDF/A-4 base

Dual Version Check

Reads both the file header version AND the Document Catalog override — shows which one takes effect.

100% Private

No server upload. Version is read directly from raw file bytes in your browser memory.

Feature Matrix

Shows which PDF features are supported at your document's version level.

Encryption Status

Detects whether the PDF is encrypted and shows the encryption method used.

Full Metadata

Extracts title, author, creator, producer, creation date, and modification date.

Acrobat Compatibility

Shows the minimum Adobe Acrobat version required to fully support your PDF's features.

Frequently Asked Questions

Why does Acrobat show a different version than the file header?

PDFs have two places where the version is stored: the file header (the first line of the file, e.g. %PDF-1.4) and an optional /Version entry in the Document Catalog dictionary. When present, the Catalog version overrides the header version. This tool checks both and tells you which one is in effect. This explains why Adobe Acrobat may display a different version than what you see in the raw file header.

Which PDF version should I use?

PDF 1.7 is the best choice for most uses — it is an ISO standard (ISO 32000-1), universally supported by all PDF readers, and supports all common features including AES-256 encryption, transparency, layers, and Tagged PDF for accessibility. PDF 2.0 is the latest ISO standard and recommended for new workflows, but some older software may not fully support it yet. PDF 1.4 is best when you need PDF/A-1 archival compliance or maximum compatibility with very old systems.

Is my PDF uploaded to a server?

Never. The PDF version is read directly from the first bytes of your file in browser memory using the JavaScript FileReader API. For metadata and catalog version, pdf-lib processes the file locally. Nothing is ever transmitted to any server. Your file stays entirely on your device throughout the entire process.

What is the difference between PDF, PDF/A, and PDF/X?

PDF is the standard document format. PDF/A is a strict subset of PDF designed for long-term archiving — it prohibits JavaScript, encryption, and external references while requiring embedded fonts and colour profiles. PDF/A-1 is based on PDF 1.4, PDF/A-2 and PDF/A-3 on PDF 1.7, and PDF/A-4 on PDF 2.0. PDF/X is a subset for print production that ensures consistent colour reproduction. PDF/UA is for universal accessibility, requiring proper tagging and metadata.

Can I change the version of a PDF?

Yes. Most PDF editors (Adobe Acrobat, Foxit, PDF-XChange) allow you to save a PDF with a specific version number. Upgrading from 1.4 to 1.7 enables additional features. Downgrading (e.g. 1.7 to 1.4) may strip features not supported in the older version. Note: simply changing the version number in the header without adjusting the content structure can create an invalid PDF — always use a proper PDF editor for version changes.

Does PDF version affect file size?

Not directly, but newer versions support better compression algorithms. PDF 1.5 introduced cross-reference streams and object streams which can significantly reduce file size for documents with many objects. PDF 2.0 includes further compression improvements. A PDF 1.7 or 2.0 file with the same content as a PDF 1.4 file may be smaller if it uses the newer compression features available in those versions.