How can I calculate the size of my applications Config Vars

Issue

Config Vars are limited to 64KB per application. The Platform will prevent you from attempting to store more than 64KB, but it can sometimes be helpful to know how much space is being used.

Resolution

You can calculate the size of your Config Vars via the CLI command:

$ heroku config --json -a APP_NAME | tr -d '[:space:]' | wc -c
   13245

Here, the Config Vars are using ~13KB of space.