Retirement Nest Egg Calculator

How to use this calculator

Enter your current age, target retirement age, current savings, monthly contribution, expected annual return, inflation rate, and desired annual retirement income in today’s dollars.

The calculator projects your portfolio at retirement and tells you whether you’re on track. If there’s a gap, it shows the monthly contribution needed to close it.

Annual Retirement Income is the most important input. Use today’s dollars. The calculator adjusts for inflation internally. If you want to spend $60,000 per year in today’s purchasing power when you retire, enter $60,000.

Expected Return should be real (inflation-adjusted) if you want everything in today’s dollars, or nominal if you prefer future dollar figures. Using a real return of 4% to 5% and a target in today’s dollars is cleaner for planning.

The formula

Where FV is future portfolio value, PV is current savings, r is annual return, n is years, and PMT is annual contribution.

For monthly contributions, use the monthly rate (r ÷ 12) and convert years to months. The result is equivalent.

The inflation adjustment you can’t skip

A $1.5M nest egg in 30 years is worth about $617,000 in today’s purchasing power at 3% annual inflation. If your target is $1.5M in today’s dollars, you actually need $3.64M in nominal future dollars.

Two ways to handle this:

Option 1: Use real return (nominal return minus inflation approximately, or precisely: (1+nominal)/(1+inflation)−1) and express your target in today’s dollars. At 7% nominal and 3% inflation, the real return is 3.88%. Use 3.88% as your return input and today’s dollar target.

Option 2: Use nominal return (7%) and express your target in nominal future dollars. For $1.5M in today’s dollars over 30 years at 3% inflation: $1.5M × 1.03^30 = $3.64M as the nominal target.

Option 1 is cleaner because everything stays in current purchasing power. Most people find it easier to think in today’s dollars than in inflated future amounts.

How much you need to save each month

The required contribution depends entirely on your target, timeline, and starting point. Here’s what reaching a $1.5M nest egg (in today’s dollars) requires at 7% nominal return:

Years Until Retirement	Starting from $0	Starting from $100,000
30 years	~$1,480/month	~$840/month
25 years	~$2,120/month	~$1,270/month
20 years	~$3,250/month	~$2,120/month
15 years	~$5,400/month	~$3,900/month
10 years	~$9,700/month	~$7,800/month

The impact of existing savings is large. Someone beginning with $100,000 needs 43% less per month than starting from zero at a 30-year horizon. That $100,000 head start is worth nearly $640 per month in reduced contributions.

Each additional 5 years of runway roughly halves the required monthly contribution. The converse: waiting 5 years to start roughly doubles what you need to save per month. This math is why starting early is not just advice but arithmetic.

The three things that determine your nest egg

Time. The most powerful lever. A dollar invested at 25 has 40 years to compound; the same dollar at 45 has 20. At 7% return, the 25-year-old’s dollar grows to 14.97 by age 65. The 45-year-old’s dollar grows to 3.87. The gap is nearly 4x from the same dollar invested in the same thing at different ages.

Return. Differences in annual return compound dramatically over long periods:

• $500 per month for 30 years at 5% = $416,000
• $500 per month for 30 years at 7% = $567,000
• $500 per month for 30 years at 9% = $769,000

The gap between 5% and 9% is $353,000 on the same $180,000 in contributions. This is why low-cost index funds matter. A fund with a 1% expense ratio at 7% gross return delivers 6% net. A fund with a 0.05% expense ratio delivers 6.95% net. Over 30 years on $500 per month, that 0.95% difference is worth roughly $100,000.

Contributions. The most controllable variable short-term. Doubling your monthly contribution roughly doubles your nest egg, all else equal. Going from $500 to $1,000 per month for 30 years at 7% adds about $567,000.

Which accounts to use

The account type affects both the growth trajectory and how you access money in retirement.

HSA (Health Savings Account). Triple tax advantage: pre-tax contributions, tax-free growth, tax-free withdrawals for medical expenses. After 65, withdrawals for any purpose are taxed like a traditional IRA. Contribution limit $4,300 for self-only and $8,550 for family coverage in 2025. Max this first if eligible.

Roth IRA. After-tax contributions, completely tax-free growth and withdrawals. No required minimum distributions on Roth IRAs. Contribution limit $7,000 per year ($8,000 if over 50). Best for people in lower tax brackets today who expect similar or higher rates in retirement.

Traditional 401(k). Pre-tax contributions, tax-deferred growth, ordinary income tax on withdrawals. Contribution limit $23,500 in 2025. Required minimum distributions start at 73. Max the employer match first (it’s an immediate 50% to 100% return on those dollars), then max the full limit.

Taxable brokerage. No tax advantages, but completely flexible access at any age. Essential for anyone retiring before 59.5 who can’t touch 401(k) funds without penalties. Long-term capital gains rates (0%, 15%, or 20%) are lower than ordinary income rates.

For most FIRE-track savers: HSA first, then Roth IRA, then 401(k) to the maximum, then taxable brokerage with any remaining capacity.

Fidelity’s age benchmarks

A useful reference for whether you’re on track for a standard retirement at 67:

Age	Fidelity Recommended	Median Actual Savings
30	1× annual salary	~$47,000
35	2× annual salary	~$87,000
40	3× annual salary	~$134,000
45	4× annual salary	~$186,000
50	6× annual salary	~$252,000
55	7× annual salary	~$314,000
60	8× annual salary	~$385,000
67	10× annual salary	~$537,000

Median actual savings fall short of the recommended multiples at every age. This doesn’t mean saving more is impossible, it means most people haven’t done it yet.

Two important caveats. First, Fidelity’s guidelines assume retirement at 67 with Social Security contributing part of your income. If you’re targeting earlier retirement, you need more at every age than these benchmarks suggest. Second, if you have a pension, the equivalent portfolio value should count: a $3,000 per month pension is worth roughly $900,000 in portfolio equivalent at a 4% withdrawal rate.

The savings rate effect

The relationship between savings rate and retirement timeline is dramatically non-linear.

Each additional dollar saved does two things simultaneously: it compounds forward toward a larger nest egg, and it reduces the size of the nest egg needed (because you spend less, so you need a smaller portfolio to fund retirement).

At $100,000 annual income:

• Save 10% ($10,000/year), spend $90,000/year: needs $2.25M FIRE number. At 7%, reaches it in roughly 32 years.
• Save 40% ($40,000/year), spend $60,000/year: needs $1.5M. Reaches it in roughly 18 years.
• Save 60% ($60,000/year), spend $40,000/year: needs $1M. Reaches it in roughly 12 years.

The jump from 10% to 40% savings doesn’t just quadruple annual contributions. It cuts the timeline by 14 years. The jump from 40% to 60% cuts another 6 years. High savings rates accelerate retirement exponentially because they work on both the accumulation side and the target simultaneously.

What to do if you’re behind

If your current savings fall short of where you’d like to be, there are a few practical paths forward.

Increase contributions now. The most direct lever. Even a temporary increase of $500 to $1,000 per month for 5 years generates $35,000 to $70,000 in additional savings, which then compounds for 20 to 30 years. A 3-year sprint can add 2 to 3 years of retirement savings.

Reduce the retirement income target. Many people build retirement budgets around their current spending without asking whether that spending actually makes them happy. If $80,000 per year sounds right but $65,000 is genuinely fine, the FIRE number drops by $375,000 and the timeline shortens.

Extend the working timeline modestly. Two extra years of contributions plus two more years of compounding can close a $200,000 to $400,000 gap, depending on income and return assumptions.

Capture the full employer match. If you’re not getting the full 401(k) employer match, fix that first. It’s an immediate 50% to 100% return on those dollars, which no investment can reliably beat.

Being behind is common. The Fidelity benchmarks show that median savers at every age fall short of recommended multiples. The important thing is knowing the gap and taking concrete steps, not treating the shortfall as inevitable.

The Roth conversion opportunity during accumulation

Most people think of Roth conversions as a retirement-phase strategy. They can also be powerful during accumulation, particularly in years of lower-than-usual income.

A job change, sabbatical, business loss, or parental leave year often creates a temporarily lower-income year. Converting traditional IRA money to Roth during those years locks in a lower tax rate on that portion of your retirement savings. Every dollar in a Roth account grows completely tax-free and comes out tax-free in retirement, with no RMDs forcing distributions you don’t need.

The math: converting $20,000 from traditional IRA to Roth in a year when you’re in the 12% tax bracket costs $2,400 in federal taxes. If that $20,000 grows to $80,000 over 25 years at 7%, the $2,400 tax payment bought $60,000 in tax-free growth. Compare that to paying ordinary income tax rates of 22% to 32% on the same $80,000 when withdrawn at 73 under RMD rules: the conversion saves $15,000 to $20,000 in future taxes.

This is one reason why FIRE practitioners who retire in their 40s before Social Security often have a 10 to 20 year window of very low taxable income. They use that window systematically for Roth conversions, filling the 10% and 12% brackets each year. After 10 to 15 years of conversions, a large portion of the traditional IRA is converted to Roth, future RMDs are reduced, and a substantial tax-free pool is available for the later decades of retirement.

The compounding power of starting early: a concrete example

The best argument for starting retirement savings early is concrete arithmetic.

Consider three people, each earning $80,000 per year and targeting a $1.5M retirement nest egg at age 65:

Person A starts at 25. Contributes $850 per month at 7% return. Reaches $1.5M at age 63. Total contributions: $387,600.

Person B starts at 35. Needs $1,880 per month to reach $1.5M by 65 at 7% return. Total contributions: $676,800.

Person C starts at 45. Needs $4,750 per month, which is likely impossible on an $80,000 salary. At a more realistic $2,000 per month, they reach only $740,000 by 65.

Person A and Person B both reach $1.5M, but A contributes $289,200 less than B. That’s 10 years of B’s contributions that A doesn’t need. The other $1.1M in both portfolios is pure compounding.

The lesson isn’t that starting at 45 is hopeless. It’s that each decade of delay roughly doubles the required monthly contribution to reach the same goal. Starting at 25 gives compounding the most time to do its work, and the effort required to reach the nest egg target stays within reach of a normal income.