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https://www.daveramsey.com/smartvestor/investment-calculator

It may be different where you live, in the UK it's often suggested that when you start out with a pension you should save minimum half your age as a percentage of your income until you retire. I.e. if you start at 41 then you should put 20.5% into your pension.

I would recommend playing around with https://www.firecalc.com/ as it seems to be a pretty customizable calculator.