The amount you need to save now depends on how you want to live after you retire. Predicting exactly how much income you’ll need in retirement is challenging because the future is uncertain. It’s a good idea to consider several scenarios. For example, if you plan to travel extensively after you retire, you may need to save more than if you plan to spend most of your time relaxing at home.
Try the AARP Retirement Calculator for a quick informational snapshot or ESPlanner Basic for a dynamic plan under several different assumptions.