Manic Inventor – web utilities that don't need to see your data

I have been building small web utilities for things I find myself needing while developing. Regex testing, JSON formatting, Base64 conversion, CSS generators, image → Data URI, etc.

I got tired of tools like these uploading data to a server, so I started building them with a simple constraint: if the task doesn't need a server, don't use one.

That turned into Manic Inventor, a collection of free tools that run locally in the browser.

Image to Data URI is one of the newer ones: https://imagetodatauri.com/

I'd be interested in feedback on whether this local-first approach is actually useful to other developers, and which tools are missing.