Your free trial should last as long as it needs to in order to show the value in what you have to offer. For creators, you might offer a free month so leads can get a sense of everything that you provide to subscribers in a month's time. Ultimately, you need to decide what works best for you and your audience. You want to provide people enough time to be able to make a decision but not so much time that you're giving away more content than you need to be.