From the very beginning of cloud, I have to admit this has been a constant struggle. Over the past several years, Amazon has offered us some great tools including cost explorer to help under costs, use, and potential opportunities to save, and reduce operating costs.
Fast forward to the end of 2022, the new AWS Cloud Intelligence, CUDOS, KPI, and Trends Dashboards are absolutely fantastic, see the link below. To take the reports a setup further, you must have your tagging setup and configured, as that can be used to further filter the costs, the results are some really powerful business and operating insights. You will be able to look at past usage and forecast for the future. The data refreshes are within 24 hours, not real-time, but pretty close.
Tech Leader Notes 