How to check minecraft accounts without the minecraft launcher

More information at wiki(dot)vg/Authentication

1. Download Postman or a similar http request creator
2. Create a request to https://authserver.mojang.com/authenticate with the POST header
3. Set the Content-Type header to application/json
4. Set the body to raw and input the following json:
   {
   "agent": {
   "name": "Minecraft",
   "version": 1
   },
   "username": "PUT THE USERNAME HERE",
   "password": "PUT THE PASSWORD HERE",
   "requestUser" : true
   }
5. Send the request
6. If a 403 code is received the details were incorrect
7. If it shows details about the user it worked

Done!
You can implement a similar thing into a script as I have done that will check lots of accounts at once.
Thanks for reading!