Then vs Than
Quick answer: Then is about time or sequence (first this, then that). Than is only for comparisons (bigger than). If you're comparing, it's always than.
Then
Adverb: at that time; next in order; in that case.
“We ate dinner, then watched a movie.”
Than
Conjunction/preposition: used to introduce the second part of a comparison.
“This puzzle is harder than the last one.”
How to remember it
thAn compares — both have an A. thEn sequences Events — both have an E.
Common mistake
'Better then ever' — comparisons take than.