Your take-home pay today
What lands in your paycheck right now, after federal + state + FICA. This is the income you live on while you save.
— / year
Per month
—
Effective tax rate
—
Annual 401(k) contribution
—
Retiring at 55 (or 65)
From paycheck to portfolio to safe withdrawal. Same inputs drive every step: how much you'll have, how much you can safely spend each year, and whether your money lasts. Change the retirement age — the whole plan recomputes.
Your 401(k) at retirement
Projected balance, with your contributions, employer match, and compounded returns. Today's dollars + nominal.
— nominal at retirement
In today's dollars —
You contribute
—
Employer match
—
Investment growth
—
Years invested
—
Safe withdrawal income (4% rule)
What you can spend per year from your portfolio without running out for ~30 years, per the Trinity Study.
— / year, in today's dollars (4% rule)
At 3.5% (more conservative)
—
Plus other income
—
Your stated need
—
Surplus / shortfall
—
How long your money lasts
Given your actual spending need (net of other income), how many years before the portfolio hits $0 — assuming 5% real returns during retirement.
— years of cushion
Money runs out at age
—
Real withdrawal % of balance
—
The plan, at a glance
—
What's next?
What this plan assumes
- 7% expected return while saving — the long-term S&P 500 average. Adjust down for a balanced 60/40 portfolio (~6%) or up for aggressive stocks (~10%).
- 3% annual inflation for the "today's dollars" line — long-term US average. The Fed targets 2%.
- 5% real return during retirement (more conservative — once you're drawing down, sequence-of-returns risk matters).
- 4% safe withdrawal rate based on the Trinity Study — historically, a portfolio that withdraws 4% inflation-adjusted from a 60/40 mix has survived all 30-year periods. 3.5% is the safer choice for early retirees (40+ year horizons).
- Tax year 2026 brackets — federal + your state's data refreshed June 2026.
- Annual compounding with end-of-year contributions. Real plans contribute every paycheck, so actual balances run slightly higher (~1% over 30 years).
This is the "is the math plausible?" sanity check. For a real retirement plan you'd want to model Social Security timing, Roth conversions, RMDs, and healthcare costs — talk to a fee-only CFP for that.