Detonating spell 'level'

[BloodandDust]

What level is a heightened cantrip considered to be for detonating spell?

Detonating spell (one action metamagic): "Your spell becomes volatile and explosive. If the next action you use is to Cast a Spell that deals damage to a single target and the spell successfully damages that target, the spell explodes, dealing splash damage equal to the level of the spell cast to adjacent creatures. Unlike normally, this splash damage doesn't apply to the target. The splash damage dealt is of the same type the spell deals."

>> Splash damage equal to the level of the spell cast

Cantrip: "A spell you can cast at will that is automatically heightened to half your level rounded up"

So, for the purposes of this feat, is a cantrip cast by a 6th level caster a 3rd level spell that would deal an extra 3 splash damage? E.g. produce flame would then be sort of a low-rent fireball, dealing 3d4 + 3 splash damage?

Handy for swarms, if true, but sacrifices an entire turn.

[Gortle]

Yes you have it right. The splash damage applies to different targets not the primary target though. The normal damage aplies only to the primary target.

So as a low rent fireball it is 3d4 or 3 fire damage.

[Megistone]

The splash damage is small, but if you can trigger a weakness it can be worth it.

[BloodandDust]

Thank you both. 'Appreciate the clarification, and yes I agree, even a small splash can make the difference sometimes.