pdf-toolkit

name	pdf-toolkit
description	Process PDF files with merge, split, rotate, compress, watermark, and password operations via a self-hosted web UI and API. Use when asked to combine PDFs, extract pages, reduce file size, add watermarks, or protect documents with passwords. Triggers include "merge PDF", "split PDF", "compress PDF", "rotate pages", "watermark PDF", "PDF password", or any PDF manipulation task.

pdf-toolkit

Self-hosted PDF processing tool. Merge, split, rotate, compress, watermark, and protect PDF files through a web UI or API.

When to use

• Merging multiple PDF files into one document
• Extracting specific pages or page ranges from a PDF
• Rotating pages that are sideways or upside-down
• Reducing PDF file size for email or web sharing
• Adding a CONFIDENTIAL or DRAFT watermark to all pages
• Password-protecting a PDF before sharing
• Batch processing multiple PDFs in sequence

Quick Start

docker compose up -d
open http://localhost:3000

API Usage

All operations accept multipart form data. Responses return a token for downloading the result.

Merge

curl -X POST http://localhost:3000/api/merge \
  -F "files[]=@first.pdf" \
  -F "files[]=@second.pdf" \
  -F "files[]=@third.pdf"
# Returns: { "token": "abc123", "filename": "merged.pdf", "pages": 62 }

Split

curl -X POST http://localhost:3000/api/split \
  -F "file=@document.pdf" \
  -F "ranges=1-8,9-16"
# Returns: { "token": "abc123", "files": [...] }

Compress

curl -X POST http://localhost:3000/api/compress \
  -F "file=@large.pdf" \
  -F "level=medium"
# level: low | medium | high

Watermark

curl -X POST http://localhost:3000/api/watermark \
  -F "file=@document.pdf" \
  -F "text=CONFIDENTIAL" \
  -F "opacity=0.2" \
  -F "position=diagonal" \
  -F "fontSize=48"

Password protect

curl -X POST http://localhost:3000/api/password \
  -F "file=@document.pdf" \
  -F "userPassword=secretpass" \
  -F "allowPrint=true" \
  -F "allowCopy=false"

Download result

curl -o output.pdf http://localhost:3000/api/download/abc123

Environment Variables

Variable	Description	Default
PORT	Server port	3000
TEMP_DIR	Temp file storage	./tmp
MAX_UPLOAD_MB	Max upload size per file in MB	100
MAX_FILES	Max files per merge	20
JOB_TTL_MINUTES	Temp file retention	60
LOG_LEVEL	debug, info, warn, error	info

Compression Levels

Level	Typical reduction	Use case
low	~20%	Print-quality documents
medium	~50%	Email sharing
high	~75%	Web thumbnails, previews

Troubleshooting

"PDF is encrypted" error

The file is password-protected. Remove the password using the Password tool first (you will need the current password), then retry the operation.

File too large

Files over MAX_UPLOAD_MB are rejected with HTTP 413. Lower the file size before uploading, or increase MAX_UPLOAD_MB in your environment.

Download link not working

Download tokens expire after JOB_TTL_MINUTES (default 60). Process the file again to get a fresh token.