Wax ring
A wax ring fails at the floor. A supply fails at the wall.
Both wet the same bathroom. They leave different clues. Mixing them leads to a new toilet on a still-leaking stop.
Look behind the toilet as well as under it.
Supply drips at the coupling. Wax-ring seepage is usually at the base, often after a flush.
A rocking toilet is a wax-ring suspect.
A dry base and a wet stop is a supply suspect.
The suite below still needs the same timeline.
Either failure can stain a ceiling. Write which one you shut off.
Questions people ask
Should I keep flushing to see the leak?
No. One observation is enough.
Can I reset the toilet myself?
Only if you are allowed to work on that fixture and the floor is not already someone else’s ceiling problem.