Ever hit this wall? You need to merge PDFs, convert images to PDF, sign a contract, or run OCR on a scanned document—but your machine doesn't have a decent PDF tool installed. So what do most people do? They Google "merge PDF free" or "convert PDF online," then immediately upload their important documents to some random website.
Here's the uncomfortable truth: you're handing over highly sensitive personal data—employment contracts, tax filings, ID copies, bank statements—to servers you know nothing about. There's zero visibility into whether those services are quietly retaining your files or repurposing your data after you hit "download."
To protect your privacy and data sovereignty in the spirit of Private Brain OS, the best answer is to bring all of this in-house—100% on your own hardware. And the Swiss Army knife that handles this beautifully is Stirling-PDF.
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### What Is Stirling-PDF?
Stirling-PDF is an open-source, browser-based PDF management application that you can spin up on your Home Server in minutes using Docker.
What makes Stirling-PDF stand out is that it bundles every feature you'd expect from those popular online PDF converter sites into a single, self-contained tool—without a single byte of data ever leaving your server. Everything processes locally, fully offline, on your own hardware.
Here's a taste of what Stirling-PDF can do:
* Page Management: Merge, split, delete, insert, rotate, or reorder pages with intuitive drag-and-drop.
* File Conversion: Convert images, Word, Excel, PowerPoint, HTML, and even Markdown to PDF—and back again—with high fidelity.
* OCR (Optical Character Recognition): Extract searchable text from scanned or photographed PDFs in Thai, English, and many other languages, so you can search within documents or copy text for reuse.
* Document Security: Password-protect files, remove passwords (when authorized), apply watermarks to deter copying, or sign documents directly on the page.
* Redaction: Black out sensitive personal data (ID numbers, addresses, etc.) before sharing documents with others.
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### Prerequisites
Before installing Stirling-PDF on your Home Server, make sure you have:
1. A Home Server with Docker and Docker Compose already installed (follow our guide on turning an old PC into a Docker-powered Home Server if you haven't set this up yet).
2. Disk space for temporary files and container configuration data.
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### Step 1: Set Up the Folder Structure and Configuration
SSH into your Home Server and create the Stirling-PDF directory:
# Create the Stirling-PDF directory
mkdir -p ~/stirling-pdf
# Navigate into it
cd ~/stirling-pdf
Next, create the container configuration file docker-compose.yml:
version: '3.8'
services:
stirling-pdf:
image: frooodle/s-pdf:latest
container_name: stirling-pdf
restart: always
ports:
- "8080:8080"
volumes:
- ./trainingData:/usr/share/tessdata # For OCR language data (e.g., Thai)
- ./extraConfigs:/configs
- ./logs:/logs
environment:
- DOCKER_ENABLE_SECURITY=false # Set to true to enable user accounts and login
- SYSTEM_DEFAULT_LOCALE=th_TH # Set default UI language to Thai
Key variables explained:
* frooodle/s-pdf:latest — the official Stirling-PDF Docker image.
* ports: "8080:8080" — maps the app's internal port to port 8080 on your Home Server (swap the left-hand number for any free port you prefer).
* ./trainingData:/usr/share/tessdata — critical for Thai-language support; this is where you'll drop Tesseract OCR language data files.
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### Step 2: Download Thai Language Data for OCR (Supercharge Thai Document Scanning)
For Stirling-PDF's OCR engine to read Thai text in scanned documents, you need to download the Thai trained data file for Tesseract OCR before starting the container.
In your terminal, inside the ~/stirling-pdf directory, run:
# Create the OCR language data folder
mkdir -p trainingData
# Download the Thai trained data file
curl -L -o trainingData/tha.traineddata https://github.com/tesseract-ocr/tessdata_fast/raw/main/tha.traineddata
(Tip: You can add other languages too—e.g., English eng.traineddata—to the same folder for bilingual document scanning.)
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### Step 3: Launch the Service and Start Using It
With your config and language files in place, start the container in the background:
docker compose up -d
Give it a moment to pull the image and boot up (Stirling-PDF is feature-rich, so the initial download may be a bit large). Once it's running, open your browser and navigate to:
http://ip-address-home-server:8080
You'll see Stirling-PDF's clean, polished interface with a full command menu and built-in help documentation displayed in Thai by default!
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### Step 4: Secure Remote Access for Use Outside the Home
If you need to convert or sign documents while away from home, or want to share a secure link with family members for contract signing and document merging, pair Stirling-PDF with Tailscale (see our guide on setting up a private VPN remote-access link).
Or, if you want an extra layer of security for browser-based access, flip the security flag in docker-compose.yml from DOCKER_ENABLE_SECURITY=false to DOCKER_ENABLE_SECURITY=true. This forces all users to log in before accessing the application.
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### The Bottom Line
Having Stirling-PDF running on your Home Server is like keeping a fully equipped, 100% secure private document office in your living room. No more worrying about your tax filings, business contracts, or sensitive records leaking through some free online converter you found on a search engine.
Beyond reclaiming Data Ownership over your most important documents, you get a fast, unrestricted system that the whole family can use—no page limits, no file caps, no ads, no data harvesting. Just your files, on your hardware, under your control.