How long should my abstract be?

You are not limited to the size of your abstract. However, faculty will be reviewing it and making it too long may make this unfavourable to review. If you think you abstract is too long, then you should create external sections that link from your main page. This can easily be done by placing double square brackets around a set of words. for example ... See details of the Bayesian algorithm used here. If readers then want more information then they can click on the link you have created.