Office Conversion on Linux, Without the Windows Tax
Even though the majority of the global cloud workload runs on Linux and many DevOps teams prefer Linux environments, many organizations are forced to keep Windows in their workflow. Especially for organizations that work with Microsoft Office filetypes, there hasn’t been another option. However, as EU concerns about data sovereignty grow and increases in SaaS costs outpace inflation, the desire for an alternative has grown. Now, with our latest update to Conversion Service, you can convert the same files without using Windows.
What does it look like to bypass the Windows tax?
Previously, there wasn’t an alternative to using Windows when working with Office documents; Microsoft Office's rendering engine has historically been the only way to get high-fidelity output, which has effectively required using Windows. This evolution of our Conversion Service means your DevOps team is free from that requirement.
The cost of using Windows can add up significantly — especially considering that it’s often a small part of the workflow. We’ve spoken to customers who are paying tens of thousands of euros a year to maintain a Windows virtual machine for the sole purpose of running Microsoft Office when converting files. The rest of their architecture can be 100% Linux, but as long as they have to run Microsoft Office, they have to shoulder that cost.
On top of the cost of maintaining a virtual machine, there’s additional licensing costs, as a user license for Office 2021, Office 2024, or Microsoft 365 are required to use Office-to-PDF via Microsoft Graph. That adds a per-seat cost to the total, along with the costs of an Azure AD consent flow and MSAL token cache that needs to be rotated and secured.
Additionally, the unnecessary complexity added to the workflow comes with additional infrastructure to manage. Before, running Conversion Service in Docker on Linux meant that the configuration had to happen on a Windows machine, even if nothing else in the workflow involved using Windows.
Moving towards stronger data sovereignty
Aside from the scale of the financial burden, many organizations are moving away from a dependency on Microsoft products for data sovereignty and security reasons. A Microsoft representative has already gone on record in court saying they can’t protect EU-based data from being accessed by U.S. authorities, even without explicit authorization from the organizations or citizens involved. If your EU-based organization is using infrastructure that falls under non-EU jurisdiction, you’re potentially exposing yourself to legal risks and the accompanying fines.
And, aside from data sovereignty concerns, having to manage both Windows and Linux servers creates an extra attack surface, environment to monitor, and system that can fail. None of these issues are ones you want to introduce into important workflows or secure environments.
This combination of concerns around security, sovereignty, and cost has generated a fair amount of momentum. Notably, there’s been a clear trend towards moving away from Microsoft specifically and using open source software more broadly. The French government recently announced they’re moving 2.5 million civil servant workstations from Windows to Linux. This initiative follows smaller migrations in both national and local governments, including Denmark, Lyon, Copenhagen, Austria, and Schleswig-Holstein, and previous open-source initiatives from Italy and Switzerland. And, while there aren’t any specific requirements in the Interoperable Europe Act around open-source software at the moment, the broader movement towards open-source software and removal of proprietary systems does improve interoperability between EU organizations.
Results from previous efforts have been promising. For example, Schleswig-Holstein is estimated to save over €15 million in 2026 alone, after finishing their migration in 2025.
Linux-native Conversion Service and what it brings to the table
Now, with the Linux-native update to Conversion Service, you can join the ranks of other organizations prioritizing data sovereignty and security, while also saving substantial amounts of money. OCR, PDF/A, digital signatures, and now Office-to-PDF run in a Docker image, without a second Windows virtual machine.
This update to Conversion Service means that there’s no Microsoft license required for Office conversion, along with no longer needing:
A Microsoft 365 tenant or Office 365 user account
A Windows server license
An Azure AD consent flow
An MSAL token cache to mount and rotate
This offers a lower operational footprint, with fewer moving parts, no cloud-conversion latency, no dependency on internet connectivity for Office files, and increased ease of operation in air-gapped environments. Using it, Word, Excel, and PowerPoint files can all be converted to PDF.
Conversion Service is optimized for speed, cross-platform deployability, and flexibility when rendering documents. That flexibility includes the ability to render complex tables, embedded charts, multi-column layouts, and/or custom fonts and logos as they originally appeared in the converted PDF. In our benchmarking against Microsoft Office output, the visual difference was consistently in the single-to-low-double-digit percent range — small enough to be imperceptible to most readers.
For documents that require maximum fidelity, customers can still use:
The Microsoft Office integration, which is the highest fidelity option available and Windows-only.
The Office for the web service option, which offers true Office Online rendering, and requires an M365 license.
Standard Converter is the right default for the majority of documents and is a clear win for any Linux-only deployment.
Save money while staying secure with Conversion Service
Your organization can start decreasing costs and improving data security and sovereignty today with this Conversion Service update. Standard Converter is the default on fresh installs and a Configurator setting change for existing installs. And .rpm and .deb packaging are coming soon, alongside the existing Docker image, so you can deploy outside containers on standard Linux distributions. If you have any questions, please reach out to our team — we’re happy to help.