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---
og_image: "/images/guides/how-to-self-host-stirling-pdf-pdf-tools-2026.webp"
title: "Self-Host Stirling PDF: All-in-One PDF Toolkit 2026"
description: "Self-host Stirling PDF in 2026: Docker setup, PDF merge/split/compress/OCR workflows, security caveats, and when it replaces ILovePDF or Adobe Acrobat."
date: "2026-03-09"
author: "OSSAlt Team"
tags: ["stirling-pdf", "pdf", "tools", "self-hosting", "docker", "2026"]
tier: 1
---

## TL;DR

[Stirling PDF](https://stirlingtools.com) (Java/Spring Boot, 78K+ GitHub stars as of May 2026, MIT-licensed core with repository-specific licensing notes) is a self-hosted PDF manipulation toolkit — a complete replacement path for Adobe Acrobat and online tools like ILovePDF or SmallPDF. Merge, split, compress, rotate, OCR, add passwords, sign, convert to/from PDF, extract pages, add watermarks — 50+ PDF operations in one web app. Privacy advantage: your documents never leave your server. Adobe Acrobat Standard costs $155/year; Stirling PDF is free to self-host, apart from server and maintenance cost.

## Key Takeaways

- **Stirling PDF**: 78K+ GitHub stars as of May 2026, MIT-licensed core with repository-specific licensing notes — 50+ PDF operations, fully self-hosted
- **Privacy**: Documents stay on your server — never uploaded to third-party services
- **OCR**: Built-in Tesseract OCR makes scanned PDFs searchable
- **Libre Office**: Converts Office documents (DOCX, XLSX, PPTX) to/from PDF
- **No file size limits**: Process multi-GB PDFs without upload restrictions
- **API**: REST API for automating PDF workflows

---

## Canonical Self-Hosted PDF Toolkit Page

OSSAlt has several Stirling PDF pages because the topic spans install, privacy, and cloud-tool replacement intent. This page is the canonical self-hosting guide for deployment and operations. If you are comparing cloud services, read [Stirling PDF vs ILovePDF](/guides/stirling-pdf-vs-ilovepdf-self-hosted-2026); if you are evaluating the broader creative/document stack, start with [best open source Adobe alternatives](/guides/best-open-source-adobe-creative-cloud-alternatives-2026).

## Operations Available

| Category | Operations |
|----------|------------|
| **Organize** | Merge, Split, Remove pages, Extract pages, Reorder, Rotate, Scale |
| **Convert** | PDF→Word, PDF→HTML, PDF→XML, Word/Excel/PPT→PDF, HTML→PDF, Markdown→PDF |
| **Security** | Add/Remove password, Add watermark, Redact text, Sign PDF |
| **Optimize** | Compress, Grayscale, Remove annotations |
| **OCR** | Make searchable, Extract text |
| **Advanced** | Compare PDFs, Repair, Flatten, Add page numbers, Add image |

---

## Part 1: Docker Setup

The official deployment surface is the Docker image published as `frooodle/s-pdf` for the lightweight build and `frooodle/s-pdf:latest-fat` when you need OCR, LibreOffice, or book/advanced HTML conversion support. Keep the service behind HTTPS, enable login before exposing it beyond a private network, and pin an image tag for production change control instead of blindly pulling `latest`.

### Without OCR (Smaller)

```yaml
# docker-compose.yml
services:
  stirling-pdf:
    image: frooodle/s-pdf:latest
    container_name: stirling-pdf
    restart: unless-stopped
    ports:
      - "8080:8080"
    volumes:
      - stirling_config:/configs
      - stirling_logs:/logs
    environment:
      DOCKER_ENABLE_SECURITY: "false"
      INSTALL_BOOK_AND_ADVANCED_HTML_OPS: "false"
      LANGS: "en_GB"

volumes:
  stirling_config:
  stirling_logs:
```

### With OCR and Office Document Conversion (Full)

```yaml
services:
  stirling-pdf:
    image: frooodle/s-pdf:latest-fat    # Includes Tesseract + LibreOffice
    container_name: stirling-pdf
    restart: unless-stopped
    ports:
      - "8080:8080"
    volumes:
      - stirling_config:/configs
      - stirling_logs:/logs
      - stirling_tessdata:/usr/share/tessdata    # OCR language data
    environment:
      DOCKER_ENABLE_SECURITY: "false"
      INSTALL_BOOK_AND_ADVANCED_HTML_OPS: "true"
      LANGS: "en_GB"
      # For Calibre ebook support:
      # INSTALL_BOOK_AND_ADVANCED_HTML_OPS: "true"
```

```bash
docker compose up -d
```

Visit `http://your-server:8080` — no login required by default.

---

## Part 2: HTTPS with Caddy

```caddyfile
pdf.yourdomain.com {
    reverse_proxy localhost:8080
}
```

---

## Part 3: Enable Authentication

By default, Stirling PDF is open. Add login:

```yaml
environment:
  DOCKER_ENABLE_SECURITY: "true"
  SECURITY_ENABLE_LOGIN: "true"
  SECURITY_INITIALLOGIN_USERNAME: admin
  SECURITY_INITIALLOGIN_PASSWORD: "${ADMIN_PASSWORD}"
```

Users can be managed via **Settings → Users** after login.

---

## Part 4: Common Operations

### Merge PDFs

1. **Organize → Merge PDFs**
2. Upload multiple files (or drag and drop)
3. Reorder by dragging
4. **Merge** → download combined PDF

### Split PDF

1. **Organize → Split PDFs**
2. Upload PDF
3. Choose: split by page range, split after every N pages, or split at specific pages
4. Download as ZIP (multiple files) or individual downloads

### Compress PDF

1. **Optimize → Compress PDFs**
2. Choose compression level: low / medium / high / very high
3. Stirling uses Ghostscript for compression — typically 50-80% size reduction

### OCR (Make Searchable)

1. **Add OCR → Add Text Layer**
2. Upload scanned PDF
3. Choose language (English, German, French, etc.)
4. Download searchable PDF — text is selectable and copyable

### Convert DOCX to PDF

1. **Convert → Office Documents to PDFs**
2. Upload `.docx`, `.xlsx`, or `.pptx`
3. Download as PDF

Requires the `-fat` image (includes LibreOffice).

### Add Password Protection

1. **Security → Add/Change Password on PDF**
2. Set user password (required to open) and/or owner password (required to edit/print)
3. Choose encryption: 128-bit RC4 or 256-bit AES

### Remove Password

1. **Security → Remove PDF Security**
2. Upload password-protected PDF
3. Enter the current password
4. Download unlocked PDF

### Watermark

1. **Add Watermark**
2. Text watermark: type text, choose position, opacity, angle
3. Or image watermark: upload image
4. Preview before downloading

---

## Part 5: Additional OCR Languages

The default image includes English. For other languages:

```yaml
volumes:
  - stirling_tessdata:/usr/share/tessdata
```

```bash
# Download additional language packs (run once):
docker exec stirling-pdf apt-get install -y \
  tesseract-ocr-deu \   # German
  tesseract-ocr-fra \   # French
  tesseract-ocr-spa \   # Spanish
  tesseract-ocr-jpn \   # Japanese
  tesseract-ocr-chi-sim  # Simplified Chinese
```

Or pre-download tessdata files:
```bash
# Download from https://github.com/tesseract-ocr/tessdata
wget -P /path/to/tessdata/ https://github.com/tesseract-ocr/tessdata/raw/main/deu.traineddata
```

---

## Part 6: REST API

Automate PDF operations programmatically:

```bash
# Merge PDFs via API:
curl -X POST "https://pdf.yourdomain.com/api/v1/general/merge-pdfs" \
  -H "Content-Type: multipart/form-data" \
  -F "fileInput=@file1.pdf" \
  -F "fileInput=@file2.pdf" \
  -o merged.pdf

# Compress a PDF:
curl -X POST "https://pdf.yourdomain.com/api/v1/general/compress-pdf" \
  -H "Content-Type: multipart/form-data" \
  -F "fileInput=@large.pdf" \
  -F "optimizeLevel=2" \
  -o compressed.pdf

# Extract pages (1-3):
curl -X POST "https://pdf.yourdomain.com/api/v1/general/extract-pages" \
  -H "Content-Type: multipart/form-data" \
  -F "fileInput=@document.pdf" \
  -F "pageNumbers=1,2,3" \
  -o extracted.pdf

# OCR a PDF:
curl -X POST "https://pdf.yourdomain.com/api/v1/misc/ocr-pdf" \
  -H "Content-Type: multipart/form-data" \
  -F "fileInput=@scanned.pdf" \
  -F "languages=eng" \
  -o searchable.pdf
```

Full API docs: `https://pdf.yourdomain.com/swagger-ui/index.html`

---

## Part 7: Batch Processing

For processing many files at once:

```bash
#!/bin/bash
# batch-compress.sh — compress all PDFs in a directory

PDF_DIR="/path/to/pdfs"
API="https://pdf.yourdomain.com/api/v1/general/compress-pdf"

for f in "$PDF_DIR"/*.pdf; do
  base=$(basename "$f" .pdf)
  echo "Compressing: $base"
  curl -s -X POST "$API" \
    -F "fileInput=@$f" \
    -F "optimizeLevel=2" \
    -o "$PDF_DIR/${base}-compressed.pdf"
done
echo "Done"
```

---

## Part 8: Configuration

```yaml
# /configs/settings.yml (created on first run)

system:
  defaultLocale: en-US
  googlevisibility: false
  enableAlphaFunctionality: false

ui:
  appName: "My PDF Tools"
  homeDescription: "Self-hosted PDF toolkit"
  appNameNavbar: "PDF Tools"

# Legal / custom footer:
  loginPageMessage: ""
```

---

## Maintenance

```bash
# Update Stirling PDF:
docker compose pull
docker compose up -d

# Logs:
docker compose logs -f stirling-pdf

# Backup config:
tar -czf stirling-config-$(date +%Y%m%d).tar.gz \
  $(docker volume inspect stirling_stirling_config --format '{{.Mountpoint}}')
```


## Why Self-Host Stirling PDF?

The case for self-hosting Stirling PDF comes down to three practical factors: data ownership, cost at scale, and operational control.

**Data ownership** is the fundamental argument. When you use a SaaS version of any tool, your data lives on someone else's infrastructure subject to their terms of service, their security practices, and their business continuity. If the vendor raises prices, gets acquired, changes API limits, or shuts down, you're left scrambling. Self-hosting Stirling PDF means your data and configuration stay on infrastructure you control — whether that's a VPS, a bare metal server, or a home lab.

**Cost at scale** matters once you move beyond individual use. Most SaaS equivalents charge per user or per data volume. A self-hosted instance on a $10-20/month VPS typically costs less than per-user SaaS pricing for teams of five or more — and the cost doesn't scale linearly with usage. One well-configured server handles dozens of users for a flat monthly fee.

**Operational control** is the third factor. The Docker Compose configuration above exposes every setting that commercial equivalents often hide behind enterprise plans: custom networking, environment variables, storage backends, and authentication integrations. You decide when to update, how to configure backups, and what access controls to apply.

The honest tradeoff: you're responsible for updates, backups, and availability. For teams running any production workloads, this is familiar territory. For individuals, the learning curve is real but the tooling (Docker, Caddy, automated backups) is well-documented and widely supported.

## Server Requirements and Sizing

Before deploying Stirling PDF, assess your server capacity against expected workload.

**Minimum viable setup**: A 1 vCPU, 1GB RAM VPS with 20GB SSD is sufficient for personal use or small teams. Most consumer VPS providers — Hetzner, DigitalOcean, Linode, Vultr — offer machines in this range for $5-10/month. Hetzner offers excellent price-to-performance for European and US regions.

**Recommended production setup**: 2 vCPUs with 4GB RAM and 40GB SSD handles most medium deployments without resource contention. This gives Stirling PDF headroom for background tasks, caching, and concurrent users while leaving capacity for other services on the same host.

**Storage planning**: The Docker volumes in this docker-compose.yml store all persistent Stirling PDF data. Estimate your storage growth rate early — for data-intensive tools, budget for 3-5x your initial estimate. Hetzner Cloud and Vultr both support online volume resizing without stopping your instance.

**Operating system**: Any modern 64-bit Linux distribution works. Ubuntu 22.04 LTS and Debian 12 are the most commonly tested configurations. Ensure Docker Engine 24.0+ and Docker Compose v2 are installed — verify with `docker --version` and `docker compose version`. Avoid Docker Desktop on production Linux servers; it adds virtualization overhead and behaves differently from Docker Engine in ways that cause subtle networking issues.

**Network**: Only ports 80 and 443 need to be publicly accessible when running behind a reverse proxy. Internal service ports should be bound to localhost only. A minimal UFW firewall that blocks all inbound traffic except SSH, HTTP, and HTTPS is the single most effective security measure for a self-hosted server.

## Backup and Disaster Recovery

Running Stirling PDF without a tested backup strategy is an unacceptable availability risk. Docker volumes are not automatically backed up — if you delete a volume or the host fails, data is gone with no recovery path.

**What to back up**: The named Docker volumes containing Stirling PDF's data (database files, user uploads, application state), your docker-compose.yml and any customized configuration files, and `.env` files containing secrets.

**Backup approach**: For simple setups, stop the container, archive the volume contents, then restart. For production environments where stopping causes disruption, use filesystem snapshots or database dump commands (PostgreSQL `pg_dump`, SQLite `.backup`, MySQL `mysqldump`) that produce consistent backups without downtime.

For a complete automated backup workflow that ships snapshots to S3-compatible object storage, see the [Restic + Rclone backup guide](/guides/automated-server-backups-restic-rclone-2026). Restic handles deduplication and encryption; Rclone handles multi-destination uploads. The same setup works for any Docker volume.

**Backup cadence**: Daily backups to remote storage are a reasonable baseline for actively used tools. Use a 30-day retention window minimum — long enough to recover from mistakes discovered weeks later. For critical data, extend to 90 days and use a secondary destination.

**Restore testing**: A backup that has never been restored is a backup you cannot trust. Once a month, restore your Stirling PDF backup to a separate Docker Compose stack on different ports and verify the data is intact. This catches silent backup failures, script errors, and volume permission issues before they matter in a real recovery.

## Security Hardening

Self-hosting means you are responsible for Stirling PDF's security posture. The Docker Compose setup provides a functional base; production deployments need additional hardening.

**Always use a reverse proxy**: Never expose Stirling PDF's internal port directly to the internet. The docker-compose.yml binds to localhost; Caddy or Nginx provides HTTPS termination. Direct HTTP access transmits credentials in plaintext. A reverse proxy also centralizes TLS management, rate limiting, and access logging.

**Strong credentials**: Change default passwords immediately after first login. For secrets in docker-compose environment variables, generate random values with `openssl rand -base64 32` rather than reusing existing passwords.

**Firewall configuration**:

```bash
ufw default deny incoming
ufw allow 22/tcp
ufw allow 80/tcp
ufw allow 443/tcp
ufw enable
```

Internal service ports (databases, admin panels, internal APIs) should only be reachable from localhost or the Docker network, never directly from the internet.

**Network isolation**: Docker Compose named networks keep Stirling PDF's services isolated from other containers on the same host. Database containers should not share networks with containers that don't need direct database access.

**VPN access for sensitive services**: For internal-only tools, restricting access to a VPN adds a strong second layer. [Headscale](/guides/how-to-self-host-headscale-tailscale-vpn-2026) is an open source Tailscale control server that puts your self-hosted stack behind a WireGuard mesh, eliminating public internet exposure for internal tools.

**Update discipline**: Subscribe to Stirling PDF's GitHub releases page to receive security advisory notifications. Schedule a monthly maintenance window to pull updated images. Running outdated container images is the most common cause of self-hosted service compromises.

## Troubleshooting Common Issues

**Container exits immediately or won't start**

Check logs first — they almost always explain the failure:

```bash
docker compose logs -f stirling-pdf
```

Common causes: a missing required environment variable, a port already in use, or a volume permission error. Port conflicts appear as `bind: address already in use`. Find the conflicting process with `ss -tlpn | grep PORT` and either stop it or change Stirling PDF's port mapping in docker-compose.yml.

**Cannot reach the web interface**

Work through this checklist:
1. Confirm the container is running: `docker compose ps`
2. Test locally on the server: `curl -I http://localhost:PORT`
3. If local access works but external doesn't, check your firewall: `ufw status`
4. If using a reverse proxy, verify it's running and the config is valid: `caddy validate --config /etc/caddy/Caddyfile`

**Permission errors on volume mounts**

Some containers run as a non-root user. If the Docker volume is owned by root, the container process cannot write to it. Find the volume's host path with `docker volume inspect VOLUME_NAME`, check the tool's documentation for its expected UID, and apply correct ownership:

```bash
chown -R 1000:1000 /var/lib/docker/volumes/your_volume/_data
```

**High resource usage over time**

Memory or CPU growing continuously usually indicates unconfigured log rotation, an unbound cache, or accumulated data needing pruning. Check current usage with `docker stats stirling-pdf`. Add resource limits in docker-compose.yml to prevent one container from starving others. For ongoing visibility into resource trends, deploy [Prometheus + Grafana](/guides/how-to-self-host-prometheus-grafana-metrics-dashboards-2026) or [Netdata](/guides/how-to-self-host-netdata-real-time-server-monitoring-2026).

**Data disappears after container restart**

Data stored in the container's writable layer — rather than a named volume — is lost when the container is removed or recreated. This happens when the volume mount path in docker-compose.yml doesn't match where the application writes data. Verify mount paths against the tool's documentation and correct the mapping. Named volumes persist across container removal; only `docker compose down -v` deletes them.

## Keeping Stirling PDF Updated

Stirling PDF follows a regular release cadence. Staying current matters for security patches and compatibility. The update process with Docker Compose is straightforward:

```bash
docker compose pull          # Download updated images
docker compose up -d         # Restart with new images
docker image prune -f        # Remove old image layers (optional)
```

**Read the changelog before major version updates.** Some releases include database migrations or breaking configuration changes. For major version bumps, test in a staging environment first — run a copy of the service on different ports with the same volume data to validate the migration before touching production.

**Version pinning**: For stability, pin to a specific image tag in docker-compose.yml instead of `latest`. Update deliberately after reviewing the changelog. This trades automatic patch delivery for predictable behavior — the right call for business-critical services.

**Post-update verification**: After updating, confirm Stirling PDF is functioning correctly. Most services expose a `/health` endpoint that returns HTTP 200 — curl it from the server or monitor it with your uptime tool.

---

*See all open source document and office tools at [OSSAlt.com/categories/productivity](https://ossalt.com).*