DEV3 PDF Merge, Split and Compress — Source Code (React + Tailwind)

Source code of the DEV3 PDF Merge, Split and Compress, a client-side PDF toolbox that merges files in drag order, splits by page ranges or every page, compresses by re-rendering pages, and rotates, deletes and reorders pages.

Download: buy a licence and the ZIP is waiting in Account → Downloads. Try it live: https://dev3.tech/tools/pdf-merge-split-compress shows the finished tool running.

What is in the download

• A standalone Vite + React + TypeScript + Tailwind CSS project: src/tool holds the tool, shared pieces sit beside it
• package.json with exact versions plus a lockfile, so npm ci works
• README.md (run, build, embed in Next.js or plain React) and an MIT LICENSE

What the code does

• Merge with drag-and-drop ordering using pdf-lib copyPages
• Range parser ("1-3, 5, 8-") with one output file per part, zipped with JSZip
• Compression presets that re-render pages through pdf.js to JPEG
• Thumbnail grid for rotate, delete and reorder

Tech stack

React 19, TypeScript, Vite, Tailwind CSS 4, jszip, pdf-lib, pdfjs-dist.

Install and customise

The How to install and How to use tabs list the steps. In short: unzip, npm ci, npm run dev, then copy the tool folder into your own app if you want to embed it.

Good to know

• A browser-only tool: there is no backend or database in the code.
• Compression rasterises pages, so text is no longer selectable in the output.
• Encrypted PDFs are refused.