To maintain your standard of living in retirement, you will need to replace roughly 70% of your annual gross employment income. Why only 70%? Because your expenses will generally be lower in retirement. However, the bigger your plans, the more you'll need to save.
A clear example
Frank is 35 years old and earns 50 000 $ a year. Below are the annual amounts he will receive from public plans if he retires at age 60, 65 or 70, as well as the amounts he will need to save starting now to replace 70% of his income.