Merge PDF Files
Combine multiple PDF documents into one file. Free, instant, and completely private.
Click or drag & drop PDF files
Add 2 or more PDF files to merge
Why Flip Caps
Simple, fast, private
100% Private
Your PDFs never leave your browser. All processing is done locally with JavaScript.
Instant Results
Merge happens in seconds regardless of the number of pages. No waiting for server uploads.
Preserves Everything
Text, images, fonts, and formatting are kept exactly as they are in the original files.
Custom Order
Drag files up or down to arrange them in exactly the order you need before merging.
Works on Mobile
Upload from your phone or tablet — no desktop required. Works in any modern mobile browser.
How It Works
Three steps to merge
Upload Your PDFs
Click the upload area or drag multiple PDF files onto the page. You can add files from your computer, phone, or cloud storage.
Set the Order
Use the arrow buttons to arrange files in the order you want them combined. The first file becomes the first section of the merged PDF.
Merge & Download
Click 'Merge PDFs' and your combined document is ready in seconds. Click download to save it to your device.
Frequently Asked Questions
Is there a limit on how many PDFs I can merge?
No. You can merge as many PDFs as your browser can handle. The practical limit depends on available memory, but merging 50+ files works fine on most modern devices.
Are my PDF files uploaded to a server?
No. All merging happens directly in your browser using JavaScript. Your files are never sent to any server, ensuring complete privacy.
Will the merged PDF lose quality?
No. Pages are copied byte-for-byte from the source PDFs. There is no re-compression or re-encoding, so quality is perfectly preserved.
Can I merge password-protected PDFs?
Password-protected or encrypted PDFs cannot be merged directly. You would need to remove the password first using a PDF unlock tool.
Does this work on Mac and Windows?
Yes. The tool is browser-based and works on any operating system — Mac, Windows, Linux, iOS, and Android.
What's the maximum file size I can upload?
There is no enforced size limit. Processing large files depends on your device's available RAM. Files up to several hundred MB work well on modern devices.
About Merge PDF
The Flip Caps Merge PDF tool lets you combine multiple PDF documents into a single file without uploading anything to a server. Whether you're consolidating invoices, assembling a report, or combining scanned documents, the tool handles it instantly in your browser.
Powered by pdf-lib, an open-source JavaScript library, all page copying is done client-side. You can merge PDFs of any size, in any order, processed entirely in your browser — your files never leave your device.
All Tools
Every tool, in one place.
All tools run in your browser. No sign-up, no upload to servers, nothing stored.
Text Tools
Text Case Converter
Convert any text between 7 case styles instantly: UPPER CASE, lower case, Title Case, Sentence case, Capitalized Case, alternating case, and Inverse case.
Letter & Character Removal
Remove any specific letter, character, or symbol from text in one click. Strip numbers, punctuation, spaces, or any custom character you define.
Duplicate Line Remover
Remove every duplicate line from a list instantly. Keep only unique lines with optional case-insensitive matching and automatic sorting.
Duplicate Word Finder
Find and highlight every word that appears more than once in your text. Quickly spot and clean up repetitive writing.
Em Dash Remover
Remove or replace em dashes instantly. Swap them for a comma, hyphen, space, or delete them entirely. Great for cleaning up AI-generated text.
Dash Remover
Remove or replace any type of dash: em dash, en dash, or hyphen. Choose your replacement character or strip them completely in one click.
Find and Replace Text
Find any word or phrase and replace every occurrence across your entire text in one click. Supports plain text and case-insensitive matching.
Sentence Counter
Count sentences, words, characters, paragraphs, and lines in any text. Get an estimated reading time based on average adult reading speed.
Remove Line Breaks
Strip unwanted line breaks to produce a clean, flowing paragraph. Perfect for fixing copied PDF or email content with hard returns.
Remove Text Formatting
Strip bold, italic, and all rich text formatting from pasted content. Convert any formatted text to clean plain text instantly.
Remove Underscores
Replace underscores in text with a space, hyphen, or remove them entirely. Convert snake_case identifiers to human-readable words.
Reverse Text Generator
Reverse any text backwards: flip character order, reverse word order, or reverse entire line order. Results appear instantly in your browser.
Alphabetical Order
Sort words or lines into A-Z or Z-A alphabetical order instantly. Supports duplicate removal and case-insensitive sorting.
PDF Tools
Split PDF
Split a PDF into individual pages or custom page ranges. Download as individual files or a ZIP archive.
Extract PDF Pages
Pick specific pages from any PDF and save them as a new document. Enter any combination of pages and ranges.
PDF to JPG
Convert every PDF page into a high-quality JPEG image. Download all pages at once as a ZIP archive.
PDF to PNG
Convert PDF pages to lossless PNG images. Perfect for presentations, web use, and image editing.
Add Watermark
Stamp any PDF with custom text. Control opacity, font size, color, position, and which pages to mark.
Add Page Numbers
Number every page of your PDF with full control over position, starting number, prefix, and suffix.
Header & Footer
Add custom headers and footers to every PDF page. Supports dynamic {page} and {total} variables.
Table of Contents
Create a professional table of contents page and prepend it to your PDF document.
Remove Blank Pages
Auto-detect and remove blank pages from scanned documents and digital PDFs.