Income Replacement Calculator
This income replacement calculator sizes the retirement income you need, the gap left after other income, and the nest egg that funds it.
What it does
The Income Replacement Calculator estimates how much annual income you will need in retirement, the gap left after pensions and other income, and the nest egg required to cover that gap at a safe withdrawal rate.
Data sources & parameters
This calculator uses standard financial formulas and runs entirely in your browser. It needs no external rate data — your result is computed only from the values you enter above.
We always strive to use the latest data for every variable so our results and reports are as accurate as possible. Even so, errors are possible — you should not rely on this tool or its report alone, and we accept no liability for any decision made based on it.
The formula
required_nest_egg = (current_income × replacement_ratio ÷ 100 − other_income) ÷ (withdrawal_rate ÷ 100)
How it works
It takes a percentage of your current salary as your target retirement income, subtracts other income you expect to receive, and divides the remaining gap by your chosen safe withdrawal rate to size the savings you need.
Where it is used
- Setting a retirement savings target from your current salary
- Seeing how a pension or rental income shrinks the amount you must save
- Testing how a more cautious withdrawal rate changes the nest egg needed
Worked example
Someone earning $80,000.00 aims to replace 70% of it, giving a target of …. After $20,000.00 of other income, the gap is …, so at a 4% withdrawal rate they need … saved.
What the income replacement calculator does
The income replacement calculator estimates how much you need to save for retirement by working back from the income you want. You choose what share of your current salary to replace, account for pensions and other income you already expect, and the tool shows the savings pot required to fund the rest. You can plan towards that figure, review it each year, and adjust it as your circumstances change.
The idea behind income replacement
You do not usually need to replace all of your salary in retirement. You may no longer be saving for retirement itself, commuting costs may drop, a mortgage may be paid off, and work-related expenses shrink, so planners usually talk about replacing a portion of pre-retirement income.
A replacement ratio of 70% means you aim to live on 70% of your final working income. Someone who plans to travel extensively, or who expects high healthcare costs, might target a higher ratio; someone with a paid-off home and a modest lifestyle might choose a lower one.
How the calculation works
First, the tool applies the replacement ratio to your current annual income to set your target retirement income. If you earn 80,000 and choose a 70% ratio, your target is 56,000 a year.
Second, it subtracts other income you expect in retirement, such as state or workplace pensions, annuities, and rental or part-time income. If those sources provide 20,000, the gap your own savings must cover is 36,000 a year.
Third, it divides that annual gap by a safe withdrawal rate, the percentage of your savings you plan to draw each year. At a 4% withdrawal rate, a 36,000 gap requires 900,000 in savings. A lower rate is more cautious and needs a bigger pot; a higher rate needs less but carries more risk of running short over a long retirement.
Reading your results
The needed retirement income is your target lifestyle cost in today's money. The annual income gap is the part of that target your own savings must fund after other income. The required nest egg is the lump sum that, drawn at your chosen rate, produces that gap year after year.
The gap shows how much of the work your existing pensions and income already do. For many people, finding that a state pension covers a meaningful share of the target makes the remaining goal look far more achievable.
Why other income matters
Other income is usually the input that moves the required nest egg most. Because savings are converted at a small withdrawal rate, every unit of guaranteed income removes many units of required savings: at a 4% rate, an extra 1,000 a year of pension income reduces the nest egg you need by 25,000.
That is why guaranteed lifetime income is so valuable, and why delaying a pension to increase its amount, or building a small annuity, can lower the savings burden sharply.
Comparing scenarios
- Try a cautious replacement ratio and an ambitious one to bracket your target.
- Lower the withdrawal rate to see how much extra saving buys a bigger safety margin against a long retirement or weak markets.
- Increase the other income figure to see the effect of any guaranteed income you can add.
- Re-run it every few years, as your salary, home, and family situation change.
Limits
The nest egg rests on assumptions that will not hold perfectly: your future salary, the replacement ratio, the reliability of other income, and the safety of the withdrawal rate. Markets vary, inflation shifts, and personal needs change, so treat the figure as a planning target.
The calculator does not model tax in detail, sequence-of-returns risk, or one-off costs like care in later life. Use it to set direction and scale, then refine the plan with more detailed tools or a qualified adviser as retirement approaches. Once you know the target, you can turn it into a monthly saving amount and a realistic timeline.
This article is general information only and is not financial advice.
About This Income Replacement Calculator
Use this income replacement calculator to get an instant estimate based on the figures you enter. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.
Frequently asked questions
How does the income replacement calculator work?
What is a good income replacement ratio?
Why do I subtract other income before sizing the nest egg?
What withdrawal rate should I use?
Does the calculator account for inflation?
Is my data kept private?
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