Will I have to pay unreal or epic the 5% royalty even if my game is free to download?

I just started using Unreal Engine and I am very happy so far, but i have a question:
Will i have to pay the 5% royalty fee to unreal/epic even if i market my game for free?
I’m not trying to find a loophole, i was just curious. I was thinking about making my first game free so i could see exactly what the game developing market was like.

5% of free is 0. If you make no profit, you pay nothing.

no 5% of a free game will be 0$ so you don’t have to pay.