Hi. I’m currently a junior at a medium sized high school in rural Maryland. I was recently introduced by my guidance counselor to parchment.com, a website that essentially chances you for colleges you are interested in. After putting in my test scores (1990, SAT 710M, 620CR, 660W, 5 on AP US Gov), my extracurriculars, (4 clubs, president of one club, swimming, XC, Eagle Scout, etc), GPA (4.00 UW, 4.31 W) and with class rank (top 3%), I was given chances to colleges I was interested in. I was given above average chances at schools such as Duke (21%), Notre Dame (40%), Emory (55%), and UMD (95%) among others. I was wondering if anyone has ever used this site to gauge their chances at acceptance at selective universities? All feedback is welcome and appreciated! Thanks! 
Parchment is only as accurate as the people reporting results back to it, and that subset is not necessarily representative of the overall student population. If you look at difference sites, you will see wildly different predictions. One thing I have noticed is that they are all pretty consistent except for a few top universities - when you get to the ones where average acceptance rates are 15% or less far more randomness creeps in. The universities with super ‘holistic’ admissions (not data driven) are the most difficult to predict.
Parchment is a garbage-in-garbage-out site. The data is self reported with no validity checks, and no way to know if the sample of self reporting participants accurately represent the applicant pool. If your school uses Naviance, look at that instead. Parchment is a parlour trick, nothing more.
@intparent @TooOld4School Thanks for the input! My school uses Naviance so I will check that out too.
Naviance is about as close as you will get to an accurate predictor. It only uses three metrics ; your school, your GPA, and your ACT/SAT. Also realize that Naviance’s results may be inaccurate because some students take both the SAT and ACT and perform much better on one or the other, and you will get weird results like students getting into Michigan with 3.7 GPA and 22 ACTs. (probably had a 2300 SAT) . You can watch the pattern on the scattergram to see of the university admissions are mostly data driven or holistic - just look for the level of clustering in the patterns.