What is the maximum file size I can process?

There is no hard file size limit. Processing happens in your browser's memory. Most modern devices handle PDFs up to 100-200 MB comfortably.

How much can I compress a PDF?

Image-heavy documents can often be reduced by 50-80%. Text-heavy documents may only compress 10-20% since text is already compact.

Can I merge PDFs with different page sizes?

Yes. The Merge PDF tool combines documents regardless of page size, orientation, or source. Each page retains its original dimensions.

Free Online PDF Tools That Run in Your Browser

8 fast, free, and private PDF tools. Merge, split, compress, rotate, watermark, and convert — everything runs 100% in your browser. No files are ever uploaded to a server.

8 tools & counting

📄 Organize

📎

Merge PDF

Combine multiple PDF files into a single document. Drag to reorder.

✂️

Split PDF

Extract specific pages or split a PDF into separate files.

🔄

Rotate PDF

Rotate all or selected pages by 90°, 180°, or 270°.

🔄 Convert

🖼

PDF to Image

Convert each PDF page to a high-quality PNG or JPEG image.

📄

Image to PDF

Convert one or more images into a PDF document.

✏️ Edit

💧

Add Watermark

Add a text watermark to every page of your PDF.

🔢

Add Page Numbers

Add page numbers to your PDF in any position.

🗜

Compress PDF

Reduce PDF file size by compressing embedded images.

🛡 Privacy first. All tools run entirely in your browser. No files are uploaded, stored, or sent to any server.

📚 PDF Guides & Resources

Learn the techniques behind efficient PDF management — from file size optimization to accessibility compliance.

How to Merge & Split PDFs Efficiently — Combining contracts, splitting chapters, and organizing multi-part documents
PDF Compression: Reduce File Size Without Quality Loss — Image downsampling, font subsetting, and optimization techniques
Adding Watermarks to PDFs — Draft stamps, confidential labels, branding overlays, and positioning best practices
PDF to Image Conversion Guide — When to use PNG vs JPEG, DPI settings, and batch conversion strategies
PDF Page Numbering Best Practices — Position formats, Roman numerals for front matter, and professional numbering conventions
PDF Accessibility Guide — Tagged PDFs, screen reader compatibility, WCAG compliance, and Section 508 requirements
PDF Security & Protection — Password protection, encryption standards, redaction vs overlay, and document signing
Optimizing PDFs for the Web — Linearized PDFs, fast web view, file size targets, and embedding vs downloading

View all PDF guides →

Why Choose PDFTools's Free Online PDF Tools?

PDFTools provides a suite of free online PDF tools built for speed, privacy, and ease of use. Whether you need to merge contracts into one file, split a large report into chapters, compress a PDF for email, or add watermarks to protect your documents — every tool runs entirely in your browser with zero server uploads.

100% Client-Side – Your Files Never Leave Your Device

Unlike most online PDF tools that upload your files to remote servers, PDFTools processes everything using JavaScript running locally in your browser. This means confidential documents, contracts, financial records, and personal files are never transmitted over the network. You can verify this by checking your browser's Network tab while using any tool.

Built for Real-World PDF Tasks

Office & Admin — Merge invoices, split reports, add page numbers to presentations, compress large files for email attachments
Students & Academics — Combine research papers, extract specific chapters, rotate scanned pages, convert lecture slides to images
Legal & Business — Add watermarks to drafts, number contract pages, merge multi-part agreements into one document
Creative & Design — Convert PDF portfolios to images, combine artwork into a PDF, compress high-resolution files for web sharing

No Sign-Up, No File Size Limits, No Rate Limits

All 8 tools are completely free with no account required. There are no paywalls, no "premium" features held back, and no artificial limits on file size or number of pages. Bookmark any tool and use it instantly.

Powered by pdf-lib & PDF.js

PDFTools uses battle-tested open-source libraries: pdf-lib for creating and modifying PDFs, and Mozilla's PDF.js for rendering pages. These same libraries power millions of applications worldwide.

Understanding the PDF Format

PDF (Portable Document Format) was created by Adobe in 1993 to share documents reliably across different computers and operating systems. Today it's an ISO 32000 open standard used by billions of documents worldwide — from tax forms and legal contracts to academic papers and design portfolios.

Why PDF File Size Matters

Large PDFs cause real problems: email providers typically cap attachments at 25 MB, slow loading frustrates web visitors, and mobile users on limited data plans may abandon oversized downloads. The main culprits behind bloated PDFs are:

Uncompressed images — A single high-res photo can add 5–10 MB. The Compress PDF tool reduces image quality intelligently while keeping text sharp.
Embedded fonts — Full font files embedded when only a subset of characters is used. Professional PDF optimization subsets fonts to include only the glyphs actually present.
Redundant objects — Copy-paste operations and repeated edits leave orphaned objects in the PDF structure.

When to Use PDF vs Other Formats

PDF — Best for documents that must look identical everywhere: contracts, invoices, print-ready designs, and formal reports
DOCX — Best when the document needs collaborative editing (Google Docs, Microsoft Word)
PNG/JPEG — Best for single-page visuals, social media sharing, or when you need to embed a page in a website. Use the PDF to Image tool to convert.
HTML — Best for web content that needs to be responsive and accessible across devices

PDF Best Practices for Professionals

Always add page numbers to multi-page documents — it makes references clear in meetings and legal proceedings. Use the Add Page Numbers tool.
Watermark draft documents with "DRAFT" or "CONFIDENTIAL" to prevent accidental distribution of unfinished work. The Watermark tool supports custom text, positioning, and opacity.
Compress before emailing — Run documents through the Compress PDF tool to ensure they stay under email attachment limits.
Split large reports into chapters — Recipients often need only specific sections. The Split PDF tool lets you extract exact page ranges.

Frequently Asked Questions

Yes, all 8 tools are completely free with no sign-up, no account, and no usage limits. There are no file size restrictions or page count limits.

Yes. Every tool runs 100% in your browser using client-side JavaScript. No files are ever uploaded to any server. Your documents stay completely on your device. You can verify this by checking the Network tab in your browser's developer tools.

There is no hard file size limit — processing happens in your browser's memory. In practice, most modern devices handle PDFs up to 100–200 MB comfortably. Very large files (500 MB+) may be slower depending on your device's available RAM.

Compression results depend on the PDF's content. Image-heavy documents (scans, photos, brochures) can often be reduced by 50–80%. Text-heavy documents with few images may only compress 10–20% since text is already compact. The Compress PDF tool shows you the before and after file sizes.

Yes. The Merge PDF tool combines documents regardless of page size, orientation, or source. You can merge a portrait A4 report with a landscape letter-size spreadsheet — each page retains its original dimensions in the combined file.

No. All tools run directly in your web browser. No installation, no downloads, no extensions required. PDFTools works on Chrome, Firefox, Safari, and Edge on any operating system.