I'm unable to track how many dyno hours and add-ons I have used in a month. The gauge in the scaling dashboard shows only a monthly estimate.
Is there any source where I can check my monthly usage balance?
Login to heroku.com and go to My Account. Scroll down to the billing section and there should be a' Current Usage' block with a 'Details' button - that will show you an invoice to date.
Direct Link: https://dashboard.heroku.com/account/billing