How much a chance increase would it be if I were to do a certification?

Hi, I’m a sophomore thinking about doing the Certified Ethical Hacker(CEH) certification over the summer. Would obtaining this certification boost my chances significantly?

chances for what? admission to college? no.

Your question is much too vague. Some colleges might be really interested in this, others won’t care, apart from the fact that you are doing something you are interested in over the summer. I suspect that most colleges will fall into the “others” category. If you are wondering if you should do it, and it involves a lot of money that will be hard to come by, no, it’s not going to be impressive enough to boost your chances for most colleges, I am guessing. If you want to do it because you’re interested, do it if you can.

The main benefit, in terms of college apps, is that it shows you did something you are interested in. That’s pretty much it, on its own. If it leads to a job or something, that’s great too.