Rachel Langlois, with Cyprus Credit Union gives a helpful timeline when it comes to saving for retirement.
How much to save: On average, we estimate that someone will need to be prepared to save at least 80% of their pre-retirement income. So for example, if someone is making $50,000 during their prime earning years, they are going to want to plan on needing at least 80% of that yearly income during retirement. In this case, it would be $40,000. The average person will spend at least 20 years in retirement (however life expectancies are increasing). So $40k for 20 years is already $800k and that is not factoring in the average inflation of 3%.
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