Encounters per Level

[Grytorm]

Generally how many encounters do you have to prepare to have a PC level up? I am kind of designing an adventure for 1st level characters and I want them to reach 2nd or 3rd level by the end. So about how many encounters would I need.

(Note, I do not have a group and I am only asking out of curiosity, and I want the ideas I have written down)

[sonofzeal]

The average is about 12, if you follow the charts.

However, we don't. Instead, we level up every second session attended - or every session, if we're two or more behind the pack.