Stirling-PDF — Free Alternative to Adobe Acrobat Pro

At a glance

GitHub repo

Stirling-Tools/Stirling-PDF

GitHub stars

96,238 (checked 11 November 2026)

Licence

MIT (per the repo LICENSE file)

Main language

TypeScript

Replaces

Adobe Acrobat Pro

Paid price it replaces

$19.99/month (annual plan, billed monthly; $29.99/month without commitment)

Best for

Offices and freelancers who merge, split, compress and sign PDFs every week and want the files to stay on their own machine.

Prices were checked on the vendor's pricing page on 11 November 2026 and may have changed since. Star counts are a snapshot from the same date.

What Stirling-PDF does

Stirling-PDF is a self-hosted web app that puts more than 50 PDF tools in one place: merge and split files, compress them, convert formats, run OCR, add signatures and watermarks, and reorder pages. You open it in a browser, drag in a PDF, and pick the tool you need. For most office work it covers about 95% of what people open Acrobat for.

The comparison is Adobe Acrobat Pro at $19.99 a month on an annual plan billed monthly ($239.88 a year; $29.99 a month with no commitment). The bigger difference is not the price but where your files go. With Stirling-PDF your documents are processed on your own machine or VPS, never uploaded to a third-party server. For contracts, invoices and other sensitive documents, that is a real privacy advantage.

The trade-off is setup. Acrobat is an installed app; Stirling-PDF is a web app you run yourself, most easily with Docker. That takes one command and a few minutes, and after that it behaves like any website on your own network. It is also genuinely multi-user: run it once on a small server and a whole team can use it.

If your PDF work is the standard office list — combine, split, compress, convert, sign — Stirling-PDF replaces the subscription and keeps your files at home. That combination is why it has nearly 100,000 stars.

Why it is worth using for free

• More than 50 PDF tools in one place — merge, split, compress, OCR, sign, watermark
• Files are processed on your own machine, never uploaded to a third-party server
• Covers about 95% of everyday office PDF work, for a team as well as one person
• Free under the MIT licence (per the repo LICENSE file); run it with one Docker command

How to use Stirling-PDF

Run it with Docker: `docker run -d -p 8080:8080 -v ./trainingData:/usr/share/tessdata -v ./extraConfigs:/configs -v ./logs:/logs frooodle/s-pdf`. Then open http://localhost:8080 in your browser, drag a PDF onto the tool you need, and download the result.

For a team, run the same container on a small VPS and share the address. No account is needed to use the tools.

Frequently asked questions