Very useful site with offline tools:
https://devtoys.app/
DevToys is free, open source and is privacy-focused on Windows, macOS and Linux! No need to use many untruthful websites to do simple tasks with your data.
It comes with a set of 30 default offline tools, including:
- Json to Yaml and Yaml to Json converter
- Base64 Text & Image converter
- JWT encoder and decoder
- Text comparer
- Hash generator