title: php game, formula to calculate a level based on exp
body: <p>Im making a browser based PHP game and in my database for the players it has a record of that players total EXP or experience.</p>
  
  <p>What i need is a formula to translate that exp into a level or rank, out of 100.</p>
  
  <p>So they start off at level 1, and when they hit say, 50 exp, go to level 2, then when they hit maybe 125/150, level 2. </p>
  
  <p>Basically a formula that steadily makes each level longer (more exp)</p>
  
  <p>Can anyone help? I'm not very good at maths :P</p>