How Will I make money from this Free Tool

We just launched Caphacker on PH (https://www.producthunt.com/post...) which is a free tool for adding captions to your videos Since there is no paid plan, People always ask me how to make from it. Other people are spending money on Paid ads. I just give away a FREE tool to gather audience Basically, it is like a lead-generation tool. Once I have a good number of users. I will build a paid plan with more features with their feedback. Free tool will also kill some competition as well. What do you think about this?