Retirement Nest Egg Calculator
Find the total portfolio size you need to fund your desired retirement lifestyle. Use it when setting long-term savings goals based on your expected income gap.
About this calculator
The nest egg target is determined by how much annual income your savings must generate beyond what Social Security and other sources already provide. First, the income gap is calculated: incomeGap = max(0, desiredIncome − socialSecurity − otherIncome). This represents the shortfall your portfolio must cover each year. The required nest egg is then: requiredNestEgg = incomeGap / (withdrawalRate / 100). This is the classic inverse of the safe withdrawal rate formula — it answers 'how large a portfolio do I need?' rather than 'how much can I spend?' A 4% withdrawal rate implies a multiplier of 25×, meaning you need 25 times your annual income gap saved. Accurately estimating Social Security benefits and other income sources is critical, as underestimating them inflates your target unnecessarily.
How to use
Suppose you want $70,000 per year in retirement, expect $20,000 from Social Security, $5,000 from a part-time rental, and plan to use a 4% withdrawal rate. Step 1 — Income gap: max(0, $70,000 − $20,000 − $5,000) = $45,000. Step 2 — Required nest egg: $45,000 / (4 / 100) = $45,000 / 0.04 = $1,125,000. You need approximately $1,125,000 saved by retirement to cover the gap. Increasing other income sources or accepting a higher withdrawal rate reduces this target.
Frequently asked questions
How do I calculate how much money I need to retire comfortably?
Start by estimating your desired annual retirement income, then subtract guaranteed income sources like Social Security and pensions to find your 'income gap.' Divide that gap by your chosen safe withdrawal rate (commonly 4%) to arrive at your required nest egg. For example, a $40,000 gap at 4% requires $1,000,000. Factors like retirement age, expected lifespan, health costs, and inflation should all influence your final target.
How does Social Security income reduce the nest egg I need to save?
Every dollar of annual Social Security benefit reduces your income gap by one dollar, which in turn reduces your required nest egg by 25 dollars (at a 4% withdrawal rate). For example, $18,000 in annual Social Security benefits means you need $450,000 less in savings. This makes delaying Social Security benefits to age 70, which maximizes your monthly payment, a powerful strategy for reducing your savings target. Even modest Social Security income can dramatically lower the portfolio size you must accumulate.
What withdrawal rate should I use when calculating my retirement nest egg?
Most financial planners suggest 3.5% to 4% as a baseline safe withdrawal rate for a 30-year retirement. Retiring early or expecting a longer retirement warrants a lower rate like 3%, which increases your required nest egg. Retiring later or having significant flexibility to cut spending in bad market years may allow a slightly higher rate. Your chosen rate has a dramatic effect: a $50,000 income gap requires $1,250,000 at 4% but $1,666,667 at 3%.