How to see memory usage in Laravel?

How to see memory usage in a Laravel app? This is for testing and to approximate how much server memory (RAM) resource I need to setup for my server usage assumptions.

How can you reduce memory usage in Laravel?

StackByte - Using chunking and cursors in Laravel to reduce query memory usage.

To see a Laravel app's memory usage, install Laravel Debugbar.

This is the easiest way to track a Laravel app's memory usage and many other things like database queries, requests, durations, exceptions etc. Saves you time from reading lots of configs, codes and other workarounds found online.

Here, a fresh Laravel 5.5 app uses 3.73MB of memory: enter image description here