More than 30 minutes might be too much information for your listeners and won't fit the interviewing time. Imagine watching a youtube video: if it is boring, you will probably skip it. Treat your presentation as a youtube video: keep it engaging, thought out, and with good sound and image quality. And, most of all, short and to the point, professional.
Professional interviewers note your time management skills.
Even if an hour is allocated for the interview, it doesn't mean you can use all that time for your presentation. Take a look at what adds up for that hour:
- Meetings usually start 2-5 minutes later than, the scheduled time (but you always should show up on time!)
- Introductions, 5-7 minutes
- Brief overview of the company, product, and team, 5-7 minutes
- Candidate's self-introduction (present yourself and talk about yourself)
- 30 minutes for portfolio presentation
- 10 minutes for presentation questions (by the way, they can come during the presentation)
- Time for candidate's questions (time is usually allocated for this because it's important for the interviewer to understand how you ask questions about the company)
Here is that hour (60 minutes). It would be naive to assume you'll have an hour to show your work. In reality, you'll have a 45-minute meeting - less than an hour! So, aim for 30 minutes for your presentation.
Interviews always end on time (even if they started late)
It is your job as a presenter to keep track of time.
When you talk to friends, they listen until the end. But in a real interview, the interviewer will simply have another meeting start, and you will say goodbye on time. It's especially awkward when the time is up, but you're only halfway there, or you finish too quickly, and important details are left uncovered.