PDF Tools – Merge, Split and Compress PDF Online

What Are PDF Merge, Split, and Compress Tools?

PDF tools are essential utilities that help you manipulate PDF documents without needing expensive desktop software. Our browser-based tool combines three powerful functions: merging multiple PDFs into one, splitting PDFs into separate files or pages, and compressing large PDFs to reduce their file size. All processing happens locally in your browser, ensuring complete privacy and security for your documents.

How to Merge PDFs Online

Merging PDFs is one of the most common document tasks for students, professionals, and anyone working with multiple PDF files. Here's step-by-step how to merge PDFs using this tool:

1. Select Merge PDF mode: Click the "Merge PDF" tab at the top of the tool.
2. Upload your files: Drag and drop multiple PDF files into the dropzone, or click "Browse Files" to select them from your computer. You can upload as many PDFs as you need.
3. Arrange the order: Your files will appear in a list. Drag them up or down to reorder pages. On mobile, use the up/down arrow buttons. The files will be merged in the exact order shown.
4. Sort if needed: Use "Sort by Name" or "Sort by Size" buttons to automatically organize your files alphabetically or by file size.
5. Set output name: In the settings panel, enter your desired filename (default is "merged.pdf").
6. Merge: Click the "Merge PDFs" button. The tool will combine all pages into a single PDF file.
7. Download: Once processing is complete, click "Download" to save your merged PDF.

Pro tip: Remove individual files from the list by clicking the delete icon if you added something by mistake. Use "Clear All" to start over with a fresh selection.

How to Split PDFs – Four Powerful Methods

Splitting PDFs gives you precise control over extracting exactly the pages you need. This tool offers four splitting methods to match different use cases:

1. Extract Page Range

Use this method when you need consecutive pages from a PDF. For example, if you have a 100-page report but only need pages 10-25 for a presentation:

• Select "Extract range" in the split options
• Enter "10" in the "From page" field and "25" in the "To page" field
• Click "Split PDF" to extract pages 10 through 25 into a new PDF
• Download your extracted pages as a single PDF file

2. Extract Specific Pages

This method is perfect when you need non-consecutive pages. Use comma-separated numbers and ranges:

• Select "Extract specific pages"
• Enter syntax like "1,3,5-8,12,20-25" to extract pages 1, 3, 5, 6, 7, 8, 12, and 20 through 25
• The tool validates your input and shows an error if page numbers exceed the PDF's total pages
• Output is a single PDF with your selected pages in order

3. Split Every N Pages

Ideal for breaking up large documents into manageable chunks. For example, split a 50-page document into 10-page sections:

• Select "Split every N pages"
• Enter "10" as the number of pages per split
• The tool creates 5 separate PDF files (pages 1-10, 11-20, 21-30, 31-40, 41-50)
• All files are packaged into a ZIP file for easy download

4. Split Into Individual Pages

This creates a separate PDF file for every single page in your document. Useful for extracting images from slides or creating individual page archives:

• Select "Split into individual pages"
• Click "Split PDF"
• Download a ZIP file containing one PDF for each page (page_1.pdf, page_2.pdf, etc.)

How PDF Compression Works

PDF compression reduces file size by re-rendering pages and optimizing their output quality. Understanding the process helps you choose the right compression level for your needs.

The Technical Process

When you compress a PDF, the tool:

1. Renders each page: Using PDF.js, each page is drawn onto an HTML5 canvas element at a specific DPI (dots per inch)
2. Converts to image: The canvas is converted to a JPEG or WebP image with adjustable quality
3. Rebuilds the PDF: Using pdf-lib, a new PDF is created with the compressed images embedded as pages
4. Outputs the result: The new PDF is saved with significantly reduced file size

Compression Levels Explained

• Light (110 DPI, 85% quality): Maintains high visual quality with moderate file size reduction (typically 20-40% smaller). Best for documents you'll print or continue editing. Text usually remains selectable.
• Balanced (90 DPI, 75% quality): Good balance between quality and file size (typically 40-60% smaller). Suitable for most sharing and archival purposes. Some text may become unselectable.
• Strong (72 DPI, 60% quality): Maximum compression for smallest file sizes (typically 60-80% smaller). Use for quick sharing when visual quality is less critical. Text typically becomes non-selectable.

Trade-offs to Understand

Quality vs. Size: Higher compression means smaller files but lower visual quality. Fine text and details may appear blurry with strong compression.

Text Selectability: Once pages are rendered to images, text becomes part of the image and can no longer be selected, searched, or copied. If you need searchable text, use Light compression or avoid compression altogether.

Processing Time: Compression is CPU-intensive. Large PDFs may take several minutes to process. The tool shows a progress bar and allows you to cancel if needed.

Common Use Cases for PDF Tools

Students

• Merge lecture notes from multiple sources into one study guide
• Extract specific chapters from textbooks for focused review
• Compress assignment PDFs to meet university upload size limits
• Split multi-page syllabi to share individual course schedules

Office Workers & Professionals

• Combine project reports, budgets, and presentations into a single client deliverable
• Extract relevant pages from lengthy contracts or proposals
• Compress large presentations before emailing to colleagues
• Split scanned documents into individual receipts or invoices

Job Seekers

• Merge resume, cover letter, and portfolio into one application PDF
• Extract specific work samples from a larger portfolio
• Compress your application PDF to meet job portal file size requirements (often 2-5 MB limits)

Government Form Submissions

• Combine multiple supporting documents (ID, address proof, certificates) into one PDF for online applications
• Compress scanned documents to meet government portal upload limits
• Extract specific pages from bank statements or utility bills

Troubleshooting Common Issues

Password-Protected PDFs

Problem: You see an error: "This PDF is password-protected."

Solution: This tool cannot process encrypted or password-protected PDFs because it runs entirely in your browser without server-side authentication. To process these files:

• Use PDF editing software (Adobe Acrobat, Preview on Mac) to remove the password protection first
• Save an unlocked copy and upload that to this tool
• If you don't have the password, you cannot process the file (this is a security feature, not a bug)

Large Files (>50MB or >200 Pages)

Problem: Processing is very slow or your browser becomes unresponsive.

Solution: Very large PDFs require significant memory and processing power:

• Close other browser tabs to free up memory
• For merge: Consider splitting your workflow—merge smaller batches first, then merge the results
• For compression: Use the cancel button if processing takes too long. Try splitting the PDF and compressing sections separately
• Desktop browsers handle large files better than mobile browsers

Corrupted or Invalid PDFs

Problem: Error message: "We couldn't read this PDF."

Solution: The PDF file may be corrupted or not a valid PDF:

• Try opening the PDF in Adobe Reader or another PDF viewer to verify it's valid
• If the PDF won't open anywhere, it's corrupted and cannot be processed
• Re-scan or re-download the original document
• Ensure files have the .pdf extension (some programs incorrectly save files as .pdf)

Compression Not Reducing File Size Enough

Problem: File size didn't decrease as much as expected.

Explanation: If your PDF is already optimized or contains mostly text (not images), compression has limited effect. PDFs with high-resolution images compress much more than text-only documents.

Privacy Explained: Browser-Only Processing

Unlike many online PDF tools that upload your files to remote servers, this tool processes everything locally in your browser using JavaScript. Here's what this means for your privacy:

• No upload: Your PDF files never leave your computer. They're loaded into browser memory and processed client-side.
• No storage: We don't store, save, or archive your files on any server. When you close the page, all data is discarded.
• No tracking: We don't log filenames, content, or metadata from your PDFs for analytics or any other purpose.
• Offline capable: Once the page loads, you can disconnect from the internet and still use the merge and split features (compress requires PDF.js which is cached).
• Secure processing: Everything happens in the sandboxed browser environment, isolated from other websites and applications.

This approach is ideal for processing sensitive documents like tax forms, legal contracts, medical records, or confidential business documents. Your files remain completely private.

Mini Glossary

Merge PDF

Combining multiple PDF files into a single document by appending pages in sequence

Split PDF

Extracting specific pages or page ranges from a PDF to create new, smaller PDF files

Compress PDF

Reducing the file size of a PDF by optimizing images, lowering resolution, or re-encoding content

DPI (Dots Per Inch)

A measure of image resolution. Higher DPI means better quality but larger file size. Standard print is 300 DPI; screen viewing is typically 72-110 DPI

Image Quality

The compression level applied to images within a PDF, measured as a percentage (0-100%). Higher values mean better quality but less compression

Password-Protected PDF

A PDF file encrypted with a password that must be entered to view or edit the contents

Browser-Side Processing

Running computations and file operations in your web browser rather than on a remote server, ensuring privacy

ZIP File

A compressed archive format used to package multiple files into a single downloadable file