Because working at a startup often involves long days and impromptu or unforeseen tasks, startup casual clothing should be comfortable and practical. Of course, when you're interviewing at a startup company, it can be difficult to get an idea of just what to wear for your interview.
If you have an interview at a startup company, nix the head-to-toe formal business attire. Rather than showing up in a black suit and dress shoes, opt for something that is relaxed but still presentable: khakis, dress pants and a nice top, for example. For the office, jeans in a variety of different styles work well.
Although the dress code at startup companies tends to be more casual than other offices, in an interview especially it's important to look professional and polished. Keep that in mind as you browse through the gallery of startup casual attire.