Spacing and padding iconography [migrated]

Wanted to practice making an icon set. I created a 24x24 px grid as a starting point. Let’s say, based off this grid, I have a rectangle icon that is 16x24 px and a square icon that is 20x20 px, but they’re both inside the 24x24 container.

I want to put 4 icons next to each other on a webpage. If I base the spacing between each icon off of the edges of the 24x24 container, wouldn’t the spacing look off since it differs between icons?

What’s the best practice to deal with this? Should I even be spacing icons off of the container size? Should my icons be different dimensions?