About the Retirement Shortfall Calculator
Find the gap between projected retirement savings and what you need, and the extra saving or later retirement to fix it.
Also known as: retirement gap, retirement savings gap, behind on retirement.
How to use this calculator
- Enter projected savings at retirement, savings needed, years to retirement, return.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
Extra PMT = gap × r / ((1 + r)ⁿ − 1)
Worked example
Using the values pre-filled in the calculator above:
- Projected savings at retirement = 650,000
- Savings needed = 1,000,000
- Years to retirement = 20
- Return = 7 %
the calculator returns:
- Shortfall: 350,000
- Extra monthly saving: 671.88
- Lump sum needed today: 86,660.72