Emanation: radius or diameter?

Hi there, Midgardians!

So my question is regarding the size of an emanation. So when a spell says: "a 30ft emanation", is it talking about its radius or its diameter?

Thanks in advance.

It is the radius(-ish). While it doesn't use that word, specifically, the definition of an emanation and a radius are basically identical.

That said, it extends from all of the occupied squares, so a large creature with a 10ft emanation would basically cover a 6x6 area (excluding itself if it wants).

Quote from sabin76 >>

It is the radius(-ish). While it doesn't use that word, specifically, the definition of an emanation and a radius are basically identical.

That said, it extends from all of the occupied squares, so a large creature with a 10ft emanation would basically cover a 6x6 area (excluding itself if it wants).

Ok, thank you! 😊

For future reference, the Rules Glossary is a good source for answers like this: https://www.dndbeyond.com/sources/dnd/br-2024/rules-glossary#EmanationAreaofEffect

It's not quite radius (slightly smaller than the actual radius), because it extends from the creature or object, not a single point.  So a medium-sized creature casting a 30' emanation (with range self) would affect a 65' diameter sphere, because it extends from their space 30' in all directions.  If it was a large creature casting the same spell, it would end up with a 70' diameter ~sphere.