Please research target company culture in advance.
E.g. looks at employees linkedin profiles, watch the videos if someone presented at conferences, etc.
For example, official dress code for interviews at Google reads "wear clothes." They mean it literally (t-shirt and shorts are ok, but please don't come bare-chested)
On the other end of the spectrum would be banks, hedge funds, etc., where you are expected to wear dress pants and shirt and a tie, if not suit.
Then there are creative workplaces (e.g. hip advertising firms) where you may actually score points with your "outrageous" look, if you are clean and well-mannered at the same time.
Same holds for physiognomy, hairdo and mods.
I'd say what matters more is how you conduct yourself and what impression you make in the first minute. If you are friendly, break the ice well, show that you can take charge of the conversation, listen and understand your interviewer (know when not take charge), feel natural (as opposed to forced) and obv., technically capable, you will do just fine.
Most of your interviewers will grasp what aspects of you are easy to change (choice to have a shower, choice of cologne, choice of attire from same category) and what are not changed on the spot (race, gender, weight, large beard).
TL;DR
In tech, if the choice is between friendly gangster and perfectly manicured asshole, almost everyone will go with the earlier.