There is no one definitive answer to this question as the value of future draft picks can vary depending on a number of factors. Some things to consider when valuing future draft picks include the strength of the team's current crop of players, the team's recent success (or lack thereof), the number of picks the team has in the upcoming draft, and the team's overall needs.
That being said, there are a few general methods that can be used to value future draft picks. One common method is to compare the pick to other picks in recent drafts and see where it falls in order of overall value. Another method is to look at the average value of picks in a particular draft slot over the last few years and use that as a baseline.
Ultimately, the best way to value future draft picks is to use a combination of these methods and come up with an estimate that makes sense for the specific situation.