Very simple multiclass spell slot calculator I made : rdndnext

CR Calculator · Encounter Generator To cast one of your artificer spells of 1st level or higher, you must expend a slot of the spell's level or higher

Experimental Elixir is a neat way to turn your 1st-level spell slots into some new effects, but it's not good enough to justify multiclassing

multiclass spell slot table Open in Calculator Previous Next Required level 85 Glyph of Spell Reflection Reduces the cooldown on Spell Reflection by 5 seconds

slot tes of olympus Spells cast from scrolls do not consume spell slots when cast, nor do most spells granted by magic items Level 0 spells are called cantrips,