Platform to Validate Ideas?

Hi, I was wondering if people knew of any platform or service whereby you can assess whether people really want your idea (if it exists). I am kind of imagining a "Product Hunt for Solvable Problems" - where people can approve or disprove relevant startup ideas. This is an idea within itself, but I was curious to understand how people currently go about the initial validation process and whether any tool remotely similar exists (it would be very useful right about now!). Thanks :)