Use Notepad++ As Offline JSON Validator

You can find plenty of websites to validate & view JSON text. JSONLint is pretty popular. But I have had issues with them when file size goes beyond 3-4 mb. I mostly use this website to validate & parse JSON. It works well with big file size. So if you have a large JSON string to validate, it can be useful.

Now if you are on Windows & already using NotePad++, you can use it as an offline JSON validator tool. Just install this plugin. Now you can validate & see JSON text in tree view inside the text editor. It works well with large text also.