The English words than and then look and sound a lot alike, but they are completely different. If this distinction is harder than it should be, read this lesson and then try again.
Than is a conjunction used in comparisons:
Technically, you should use the subject pronoun after than (e.g., I), as opposed to the object pronoun (me). However, English speakers commonly use the object pronoun.
Then has numerous meanings.
1. At that point in time
2. Next, afterward
3. In addition, also, on top of that
4. In that case, therefore (often with "if")
The Bottom Line
Than is used only in comparisons, so if you’re comparing something use than. If not, then you have to use then. What could be easier than that?