In our Integration projects, especially nowadays with Azure Integration Services, we sometimes need to work with Base64 strings. This is very common in some connectors inside Logic App, where the request or response is in Base64, like the Service Bus or the HTTP. And when we need to debug or troubleshoot our solution or business process, we need to understand what the request and response payload are. That means that we need most of the time to decode the Base64 string.
And I know what you guys are thinking… I also was thinking that way! Why do you need a Windows tool if we have plenty of online tools like https://www.base64decode.org/ that can easily do the job simply and fashionably?
📝 One-Minute Brief
Introduces a simple Windows Base64 Decode tool that helps quickly decode Base64‑encoded content, making it easier to inspect payloads, troubleshoot integrations, and analyze encoded data.
And my straightforward and honest answer is privacy/security! The problem with using these online tools is that we never know behind the scenes what they are doing. Are you sure that they are not keeping logs of the inputs we provide and the outputs? That is the magic question because we often have sensitive (private) information on those Base64 strings, like a connection string or usernames and passwords. And we need to be careful about where we put this information.
I have an amazing Ethical hacking friend, Nino Crudele, and every time I speak with him about security, I’m always more suspicious about how to use specific tools available on the web or, in general, how to secure my personal stuff and my solutions. And even speaking with Michael Stephenson, something that we try to do regularly, we share these concerns, and it was Michael who raised my suspicions about the decode online tools. Since that talk, I have stopped using them and decided to create my personal tool.
Base64 Decode Windows tool
This is a very simple Windows tool that allows you to decode your data. This is a handy tool if you have to deal with Base64 format.

To not raise the same suspicions about this tool, the source code is available on GitHub!
Download
Hope you find this useful! So, if you liked the content or found it useful and want to help me write more content, you can buy (or help buy) my son a Star Wars Lego!
Credits
- Luis Rigueira | Member of my team and one of the people responsible for developing this tool.