Retirement / FIRE Calculator
Project your nest egg, find your FIRE number, and see how inflation eats into nominal projections.
Nest Egg Growth (Nominal)
How Much Do You Actually Need to Retire?
The most useful single number in retirement planning is your FIRE number: roughly 25 times your annual spending in today's dollars. It comes from the 4% rule — if you withdraw 4% of your portfolio in year one and adjust the withdrawal for inflation each year afterward, the money has historically lasted 30+ years across the great majority of U.S. market scenarios. If you spend $60,000 per year today, your FIRE number is $60,000 × 25 = $1.5 million (in today's dollars). This calculator adjusts that figure for inflation so you see the actual dollar amount you'll need at retirement, not just today's equivalent.
Three scenarios for the same target nest egg
Target: $1.5M nest egg by age 65 (~$60K/year retirement income at a 4% safe withdrawal rate). Assumed return: 7% nominal.
| Starting Age | Required Monthly Contribution | Total Contributed |
|---|---|---|
| 25 | $570 | $273,600 |
| 35 | $1,170 | $421,200 |
| 45 | $2,610 | $626,400 |
The 25-year-old gets to the same finish line for less than half the money — because their early contributions had 40 years to compound. Every decade of delay roughly doubles the monthly contribution required to hit the same target.
The 4% Rule — Where It Comes From and What It Misses
The 4% rule originates from the 1998 Trinity Study, which analyzed every rolling 30-year period in U.S. stock and bond markets from 1926 onward. The researchers found that a portfolio of 60% stocks / 40% bonds, withdrawing 4% of the starting balance in year one and adjusting for inflation each year, had a 96% success rate over 30 years.
What it gets right: a robust starting point for conservative 30-year retirement planning in a developed-market portfolio. It's stood up to revision and recalculation many times in the 25+ years since.
What it misses:
- Time horizon: 4% was designed for 30-year retirement. Early retirees needing 40-50 years should plan 3.25-3.5%.
- U.S. exceptionalism: The data is dominated by the most successful capital-market century in history. International data suggests 4% might be optimistic.
- Sequence of returns risk: A bad decade right after retirement is more damaging than a bad decade midway through. The rule doesn't dynamically adjust.
- Flexibility: Real retirees adjust spending; the rule assumes a rigid inflation-adjusted withdrawal.
Why Inflation Is the Silent Killer
A dollar today won't be a dollar in 30 years. At 3% inflation — the long-run U.S. average — $60,000 of buying power today requires roughly $145,000 in 30 years to maintain the same lifestyle. Most retirement calculators show nominal dollars (which look great); this one shows both nominal and real so you see your true position. The real number is the one that matters for planning the lifestyle you actually want.
The FIRE Math
FIRE (Financial Independence, Retire Early) flips conventional retirement planning on its head. Instead of working until 65, the goal is to save aggressively (often 50%+ of income) until your portfolio reaches 25× your annual spending — then work becomes optional. The math is dominated by your savings rate, not your absolute income:
| Savings Rate | Years to FI (from $0) |
|---|---|
| 10% | ~51 years |
| 15% | ~43 years |
| 25% | ~32 years |
| 40% | ~22 years |
| 50% | ~17 years |
| 65% | ~10.5 years |
| 75% | ~7 years |
(Assumes 5% real return, you live on the post-savings portion of your income.) Notice that the math doesn't care about your absolute income — it cares about the percentage. Someone earning $80k and saving 50% reaches FI on the same timeline as someone earning $40k and saving 50%.
Don't Forget Social Security
For U.S. retirees, Social Security typically covers a meaningful slice of retirement income — $1,500–$3,500 per month depending on your earnings record. If you're planning for traditional retirement age, subtracting your expected Social Security from your desired income substantially reduces the portfolio you actually need. Early retirees often plan without it as a margin of safety.
Quick check: If you're 40, earning $80k, with $100k saved already, and saving $1,000/month at 7% real return — you'll have about $1.1M at 65 (in today's dollars). Whether that's enough depends on your planned spending. If you spend $40k/year, you're set. If you plan to spend $80k/year, you need to ramp up.
Tax-Advantaged Account Order
Where you save matters as much as how much. The standard priority order for a U.S. worker:
- 401(k) up to the employer match — never leave free money on the table.
- HSA (if HDHP-eligible) — only account with triple tax advantage.
- Roth IRA — tax-free growth, flexible withdrawals.
- Back to 401(k) up to the annual limit.
- Taxable brokerage for anything beyond.
Maxing tax-advantaged accounts over a career can be worth hundreds of thousands of dollars in avoided taxes compared to investing only in taxable accounts.
Common Retirement Planning Mistakes
- Underestimating healthcare costs. Fidelity estimates a 65-year-old couple needs ~$315,000 (in 2024 dollars) for out-of-pocket medical costs through retirement.
- Ignoring sequence-of-returns risk. Retiring into a bear market with no cash buffer can permanently damage a portfolio.
- Counting home equity as retirement savings. Your home is where you live, not a spendable asset (unless you genuinely plan to downsize and pocket the difference).
- Forgetting taxes on withdrawals. $1M in a Traditional 401(k) is not $1M of spending power — it's closer to $750-850k after taxes.
- Stopping investing during downturns. The math relies on staying invested across full market cycles.
- Lifestyle creep. Every raise that goes to spending increases the nest egg required to maintain it after retirement.
Frequently Asked Questions
Is 7% a realistic return assumption?
For a diversified long-horizon stock-heavy portfolio, yes — it's roughly the inflation-adjusted historical U.S. average. For a 60/40 stock/bond mix, 5-6% real is more realistic. For an all-bond portfolio, plan 2-3% real.
Should I include Social Security in my projection?
If you're planning for traditional retirement age (62+), yes — subtract expected benefits from your desired income. Early retirees often plan without it as a margin of safety, and because policy changes between now and then could reduce benefits.
What about taxes?
This calculator shows pre-tax growth. Real after-tax outcomes depend on whether your money sits in tax-deferred (401k, Traditional IRA — withdrawals taxed as ordinary income), tax-free (Roth, HSA — qualified withdrawals tax-free), or taxable accounts (capital gains rate when sold).
What if I'm starting late?
If you're 50+ with little saved, you can use IRS catch-up contributions (extra $7,500/year to 401k, $1,000 to IRA), consider delaying retirement (each additional year working has an outsized effect), and may need to plan a lower withdrawal rate (3.5%). The math is harder but rarely hopeless.
What's a safe withdrawal rate for a 50-year retirement?
Early-retirement researchers typically recommend 3.25-3.5% for 50+ year horizons, vs the classic 4% for 30 years. Some prefer dynamic strategies (Guyton-Klinger guardrails, variable percentage withdrawal) that adjust spending based on portfolio performance.
Should I include my home equity in my net worth for retirement?
Usually no. Your home is where you live, not a retirement asset you can spend. Some people downsize at retirement and capture the difference, but counting home equity as part of your nest egg is generally optimistic accounting.
What's the difference between a Roth and Traditional account?
Traditional: contributions reduce taxable income now; withdrawals taxed in retirement. Roth: contributions are after-tax; withdrawals tax-free. Roth wins if you'll be in a higher tax bracket later, or if you want tax-free growth as a hedge.
How does this differ from a 401k calculator?
A 401k calculator usually models tax-deferred growth and employer matching specifically. This calculator is account-agnostic — enter your total monthly contribution across all retirement accounts and treat the result as a pre-tax projection.