I’m a senior which means I’m starting college interviews soon. I want to dye my hair(which is naturally brown) a silver-grey color(similar to Billie eilish’s past color). However I’m concerned that this could hurt my interviews and such, does anyone have any insight?
I wouldn’t worry about hair color for college interviews. Jobs maybe depending on your field.
If you were my kid, I would ask you to wait. You never know what someone is going to have an idiosyncratic response to it. Will it matter? Probably not. Could you be the unlucky one who gets the old fashioned interviewer who thinks it’s gross? You never know. I would err on the side of caution, and I had hair every color of the rainbow when I was your age.
If you’re planning to be an art major, yes. Business major - no. STEM major - hard to tell, depends on the interviewer.
Depends on what college and what major. But really, why hide who you are? If the school doesn’t like the real you then it isn’t a fit.
You’ve waited this long… why not wait until the interviews are over?
On the other hand, if you do color your hair, then be a bit conservative in what you wear to the interview.
Also I think that admissions people are aware that young people experiment with their hair and I don’t think would hold that against you.
You are concerned. So just wait. Trust your gut on this one. When you no longer feel at all iffy about the color, that will be the time to go ahead with it.
Just FYI - I don’t think alumni interviews matter much in college admissions. I used to interview for my college and I know for a fact that it didn’t matter to them - we were more of an outreach warm-fuzzy for anxious applicants. Unless you are applying to extremely stodgy places I can’t image silver hair dye would faze anyone anyway.
If it’s going to make you feel less confident instead of more confident in your interviews, just wait. I don’t think it matters, for the record, but if you are going to be sizing up the interviewer’s reaction it’s not worth it.
I’ve learned that you can’t always predict exactly how a new color will turn out . I’d wait 
My daughter has completed one interview with purple hair, one with blue, and her next will be with orange. That’s who she is though- rainbow-haired, pierced, outgoing, and colorful. She figures they should be seeing what they’ll get if she is admitted, so she’s fully herself. You sound unsure though, and having confidence and ease in your interview is way more important than any hair color.
I’d wait until after the interviews, unless, as @yucca10 mentioned, if you are planning to be an art major.
Don’t assume interviews don’t matter. They’re a firsthand look, “eyes on.” I think they’ve seen odd colors before but take bopper’s advice to blend in some conservative.
This CC filtering of what matters, “just be you,” is counterintuitive.
According to the OP their “real you” is brown-haired.