About YourFIREPath, FIRE Calculator
About YourFIREPath

A FIRE Calculator That Actually Does the Tax Math

Most retirement calculators ask for your savings rate and spit out a number. They skip the part that matters most for early retirees: taxes on every dollar you withdraw. YourFIREPath was built to fix that.

This site is free, runs entirely in your browser (no data ever leaves your device), and is built for people serious about financial independence and early retirement.

About the Author
Hi, I'm Kari.

I'm an electrical engineer, and I first found FIRE right after I graduated and landed my first real job. The thing that hooked me wasn't a spreadsheet — it was reading Mr. Money Mustache and seeing that the math actually worked, that someone had done it and come out the other side with a genuinely good life. What got me specifically was that he and his wife reached financial independence and then had kids. That combination stuck with me: being FIRE'd, or close to it, by the time I wanted to start a family — so that staying home was a choice I could actually make, not something I had to hope for.

I took the early steps seriously from the start. When I graduated I lived with my parents for just over a year, paid off my student loans, and saved as aggressively as I could before moving out. When I finally did, I bought a three-bedroom townhouse unit in a fourplex and rented out both spare rooms to roommates. My mortgage was around $2,000 a month; my roommates covered about $1,000 of it and split utilities with me. It wasn't glamorous but it worked. House hacking before I knew it had a name.

Eventually I moved in with my boyfriend and turned the townhouse into a rental. My mortgage dropped to about $1,590 once my property taxes came in lower than initially estimated and I was able to drop PMI. The unit rents for $1,800 now — after an 8% property management fee I clear roughly $1,650 a month, which just about covers the mortgage. I essentially break even on cash flow, the mortgage interest gets written off my taxable income, and the equity keeps building in the background.

Running my own numbers through the calculator I built here, I'm about 41% of the way to my full FIRE number. I'm roughly 4 years from Coast FIRE and 7 years from FIRE — those estimates include real tax math, which is why I built this in the first place. Every calculator I tried gave me a number without accounting for what taxes would actually cost me on every withdrawal dollar. As an engineer, that gap bothered me enough to fix it.

I stepped away from FIRE for a while and came back recently — honestly because of AI. The tech industry has had a rough few years with layoffs, and watching how fast things are moving makes the question of job security feel more urgent than it used to. I don't know exactly when AI changes my field in ways that are hard to predict, but I'd rather be financially prepared than not. That urgency is what pulled me back to the numbers and eventually to building this site.

I'm not a financial advisor. I'm an engineer who ran the numbers obsessively for my own life and wanted a tool that actually did it right. Everything here is based on published research, IRS rules, and the same math I use for my own planning. I hope it helps you the way building it helped me.

What Frugality Actually Looked Like

When I moved back in with my parents after graduating, I made a decision to spend as close to nothing on wants as I possibly could. COVID hit right around the same time, and I suddenly needed a home office setup. I didn't have a desk or a chair. So I pulled my futon up to a TV stand and worked like that for a while. Eventually I upgraded to a $20 beer pong table from Walmart and a dining room chair, which felt like a genuine improvement at the time.

When I finally moved into my own place I got most of my furniture for free or from Ikea and Wayfair. It was functional, it worked, and I didn't think much about it. A friend came over once and asked me why I had nothing on my walls. I hadn't even noticed. I was so focused on only buying things I actually needed that decoration had never crossed my mind.

The coffee situation was maybe the most committed I got. I used to stir ground coffee directly into water, let the grounds settle to the bottom, and drink it that way. Eventually I got a French press — a $15 one from Walmart. The instructions say to use fine-ground coffee but regular grounds work fine in a cheap press, I can confirm.

I don't live like that anymore, but my fixed expenses are still genuinely low. I still drive the car I had in college. My husband and I live in a one-bedroom apartment and our total for rent, parking, and internet is around $1,250 a month. It's not deprivation — it's just that the lifestyle upgrades we skipped early on never felt necessary enough to add back in. The freedom the savings bought feels worth a lot more than the things we didn't buy.

I say all of this not to brag about how frugal I was, but because I think it matters that the person behind a FIRE calculator has actually tried to live the thing. I've run these numbers for my own life. I've made the tradeoffs. The math on this site is the same math I use.

What Is FIRE?

FIRE stands for Financial Independence, Retire Early. The core idea: save and invest enough that your portfolio generates more income than you spend - permanently. At that point, work becomes optional.

The math is built on the 4% rule: research shows a portfolio of stocks and bonds can sustain a 4% annual withdrawal indefinitely. That means your "FIRE number" is 25× your annual spending. Hit that number, and you're financially free.

Lean FIRE
20× spending
Frugal lifestyle, 5% withdrawal
FIRE
25× spending
4% rule, comfortable lifestyle
Fat FIRE
33× spending
3% withdrawal, abundant lifestyle
Coast FIRE
Stop contributing
Growth alone reaches your number

What Is a Savings Rate - and Why Does It Matter So Much?

Your savings rate is the percentage of your income you invest each month. It's the single most powerful variable in your FIRE timeline - more than your investment returns, more than your income. Here's why: a higher savings rate means you're accumulating wealth faster and proving you can live on less, which means your FIRE number is smaller.

The table below assumes you're starting from $0 and earning 7% annual returns. The difference between a 20% and 50% savings rate is roughly 20 years of your life.

Savings RateYears to FIRERetire Age (start 30)
10%4373
20%3767
30%2858
40%2252
50%1747
60%12.542.5
70%8.538.5

Use the Savings Rate Calculator (under Tools in the nav) to calculate yours instantly. Most Americans save 5–10%. Most FIRE seekers target 40–60%.

Withdrawal Rate & Drawdown: How You Live Off Your Portfolio

Once you retire, you stop adding to your portfolio and start drawing from it. The withdrawal rate is the percentage of your portfolio you spend each year. If you have $1,000,000 and spend $40,000, your withdrawal rate is 4%.

The famous 4% rule (from the 1994 Bengen study and 1998 Trinity Study) found that a 4% withdrawal rate has survived every historical 30-year period in US market history - including the Great Depression, the 1970s stagflation, and the dot-com crash. The math works because your portfolio keeps growing even while you withdraw: in good years it grows faster than you spend, building a buffer for bad years.

5% - Lean FIRE
More aggressive. Smaller portfolio needed but less margin. Fine if you can cut spending in down markets.
4% - FIRE
The research-backed sweet spot. 95%+ success rate over 30 years. The standard target.
3% - Fat FIRE
Ultra-conservative. Portfolio nearly always grows. Best for very long retirements (40–50 years).

Drawdown refers to the year-by-year process of spending down your accounts in retirement. The order matters enormously for taxes. The calculator's default strategy - spend taxable accounts first, then fill low tax brackets with Traditional withdrawals, then Roth last - is designed to minimize the total taxes you pay over your entire retirement.

The Bridge Period: Retiring Before 59½

Most FIRE seekers want to retire in their 40s or early 50s - well before the IRS allows penalty-free access to retirement accounts at age 59½. Withdraw from a Traditional 401(k) before then and you'll owe a 10% penalty on top of ordinary income tax.

The "bridge period" is the gap between when you retire and when you turn 59½. During this window, your spending comes from sources that aren't penalized:

  • Taxable brokerage account - no restrictions, no penalty, taxed at favorable long-term capital gains rates
  • Roth IRA contributions - you can always withdraw what you put in (not the earnings) tax and penalty free
  • Cash / HYSA - fully liquid, earns interest while you hold it

Once you hit 59½, the floodgates open: Traditional 401(k) and IRA withdrawals are fair game. At 73, the IRS requires you to start taking Required Minimum Distributions (RMDs) - mandatory yearly withdrawals calculated as a percentage of your account balance. The calculator models all of this in the year-by-year plan.

How the Calculator Works

The calculator is built in four steps, each adding more accuracy. You can stop after Step 1 for a quick answer, or go deeper for a full retirement plan.

1
Basic FIRE date
Enter your pre-tax income, state, annual spending or savings, current age, and net worth. The calculator immediately shows your four FIRE tier targets (Coast, Lean, FIRE, Fat) and how many years until you reach each one. Federal income tax, state tax, and FICA (Social Security + Medicare) are all calculated automatically.
2
Tax refinements
Add your 401(k) contribution to reduce your taxable income. You can also override any tax rate if you know your actual effective rates - useful if you have complex tax situations, deductions, or live in a city with local income tax. This step makes your FIRE targets significantly more accurate.
3
Account balances & allocation
Enter your current balances across account types: Cash/HYSA, Taxable Brokerage, Roth 401(k), Roth IRA, and Traditional 401(k). The calculator projects each account forward to retirement and adjusts your FIRE targets based on the real withdrawal taxes your account mix will generate. A dollar in a Traditional 401(k) costs more to spend than a dollar in a Roth IRA - this step models that difference precisely.
4
Year-by-year retirement plan
Once your accounts are set, the calculator generates a year-by-year withdrawal simulation from your retirement date through age 90+. It models the "bridge period" before 59½ (when retirement account penalties apply), Required Minimum Distributions starting at age 73, and the optimal order to draw from each account to minimize lifetime taxes. You can download the full plan as a CSV.

Methodology & Assumptions

The calculator uses the following data and assumptions. These are updated annually where the IRS publishes new figures.

  • Federal income tax: 2024–2025 marginal brackets (10%, 12%, 22%, 24%, 32%, 35%, 37%)
  • Standard deduction: $14,600 (2024), applied to traditional withdrawals in retirement
  • FICA: 6.2% Social Security (up to $168,600) + 1.45% Medicare + 0.9% Additional Medicare Tax above $200,000
  • 401(k) limit: $23,500 (2025 IRS limit)
  • Roth IRA limit: $7,000 with phase-out starting at $146,000
  • Long-term capital gains: 0% / 15% / 20% brackets applied to taxable brokerage withdrawals (assumed 50% of gains are long-term)
  • RMDs: IRS Uniform Lifetime Table, starting at age 73 (SECURE 2.0 Act)
  • State tax: Flat effective rates for all 50 states + DC. State retirement income exclusions are not modeled.
  • Default growth rates: 7%/year for invested assets, 2%/year for cash/HYSA
  • Withdrawal order (post-59½): Taxable first → bracket-fill Traditional → Roth last, to minimize lifetime taxes
  • Inflation: Applied to annual spending in the retirement simulation
Not financial advice. This calculator is for educational and planning purposes only. Tax laws change, and individual situations vary. Always consult a qualified financial advisor or CPA before making retirement or investment decisions.