There is a serious problem with the state of simple development tools on the internet.
Most of the websites providing simple encoders/decoders/formatters/prettifiers are filled with ads and popups which makes it annoying and risky to use.
And then there is also a huge problem with privacy and leaking any private data that is used on any of these websites.
Although it is impossible to replace them altogether, let me introduce you to DevRider, a new open source to provide some of the common tools in an extensible desktop application.
Which means no tracking and it guarantees data safety as everything stays on your machine.
Along with these tools, there is also a curated code snippets repository with multiple supported languages.
Please checkout the project page to download application package for Mac or Windows.