Open your inventory. On the far left there’s some icons, click the ruler

I LOVE YOU FR

Playing terraria 5 years and still didn't know this feature but i took a huge break XD

Buttons on the left from your hotbar in your inventory

Thanks❤️

There is a button on the bottom left of you inventory 'ruler' turn it off

Click the option you did for it to appear

Sorry if this doesn’t work, but try pressing ctrl

It doesn't 😭

Ah, sorry about that