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Reach FI · savings rate

Savings Rate to FI — years to independence

Most FIRE calculators hand you one clean date built on a made-up return. This one decomposes the growth rate you actually keep — market return − fund expense − advisory fee − tax drag, deflated to real dollars — solves the years-to-FI equation in closed form, and reports a range (p5 / median / p95) from 1928–2025 rolling real returns. Estimate, not advice.

S&P 500 total return · Damodaran · asOf 2026-01 CPI-U · BLS · asOf 2026-01 SWR · Morningstar · asOf 2025-12 Updated 2026-07-22

Assumptions

live · closed-form solve
Take-home pay. Spending is what you don't save: income × (1 − savings rate).
Already-invested assets (today's dollars). The closed form handles a head start exactly.
Share of after-tax income invested each year. Drag it and watch the FI date slide.
Default 10.02% = geometric mean of S&P 500 total return 1928–2025 (Damodaran, asOf 2026-01). A historical statistic, not a projection.
Default 3.03% = geometric mean of CPI-U Dec/Dec 1928–2025 (BLS, asOf 2026-01). Applied via Fisher, not naive subtraction.
ICI 2025 asset-weighted averages: index mutual fund 0.05 · index ETF 0.14 · active mutual fund 0.40.
0 if DIY. Typical human-advisor AUM fee ≈ 1.00 (Datos/Envestnet 2026 study avg 0.96%). See the tornado for what it costs in years.
Account tax drag
Morningstar tax-cost ratio averages (asOf 2025-12). Category averages, not your personal tax rate.
Early retirees have longer horizons: Morningstar's 90%-success rate drops from 3.9% at 30yr to 3.3% at 40yr. Rates for 45–50yr horizons are not published; 3.3% is the longest-horizon estimate available.
Set your inputs to project the years-to-FI range.
FI number Range p5–p95
Median path (p50 real return) Range across 1928–2025 returns (p5–p95)
Set your inputs — this solves the years-to-FI equation across the full spread of historical returns, not one lucky number. Markets vary, so the honest answer is a range, not a single date.

Projected portfolio at the median FI horizon

real $ · p5 · median · p95

Real portfolio value at the median years-to-FI horizon, across 1928–2025 rolling return outcomes: coral = the p5 (weak-market) shortfall, green = median (≈ your FI number), lime = the p95 (strong-market) surplus. This is return-level uncertainty, not a sequence-of-returns simulation.

Savings rate → years to FI

curve with return-level band

X axis: savings rate 5–85%. Aqua = years at your decomposed rate; the shaded fan spans the p25–p75 of rolling historical real returns net of your fees; the mint tick marks your savings rate. Years are capped at 60 for display.

Fee tornado — in years, not basis points

Δ years to FI

Each bar re-solves years-to-FI with the extra annual fee dragged off the market return. Fees compound against you for the whole accumulation, which is why a flat-sounding 1%/yr shows up as years of additional work.

Real net return (your decomposition)
Historical real returns p25 / p50 / p75
Methodology & sources
Show the math
Set your inputs to see the worked numbers.
Assumptions & sources
AssumptionValueSource · asOf
Market return anchor 10.02%/yr nominal (editable) Geometric mean of S&P 500 total return 1928–2025, Damodaran (NYU Stern) · asOf 2026-01
Inflation anchor 3.03%/yr (editable) Geometric mean of CPI-U Dec/Dec 1928–2025, BLS · asOf 2026-01 · Fisher deflation, not subtraction
Fund expense presets 0.05 / 0.14 / 0.40 %/yr ICI, Trends in the Expenses and Fees of Funds 2025 (asset-weighted) · asOf 2025-12
Advisory fee preset 1.00%/yr typical AUM Datos Insights & Envestnet MoneyGuide, 2026 fee study (avg 0.96%) · asOf 2026-01
Tax drag presets 0 / 0.7 / 1.9 %/yr Morningstar tax-cost ratio averages, taxable equity ETF / mutual fund · asOf 2025-12
SWR presets 3.9% @30yr · 3.5% @35yr · 3.3% @40yr Morningstar, The State of Retirement Income 2026 (90% success, 30–50% equity) · asOf 2025-12 · plus the classic 4% (Bengen/Trinity)
Band construction p5/p50/p95 rolling real returns 1928–2025 windows matched to your horizon (5–40yr) · return-level uncertainty only, not sequence-of-returns risk

Textbook cross-check: at a 5% constant real return and 4% SWR, a 50% savings rate solves to ≈17 years and 75% to ≈7 years — the classic shockingly-simple-math anchors, reproduced by this engine's closed form (tests/verify_savings-rate-to-fi.mjs). All dollars are real (today's) dollars; income and savings are assumed to keep pace with inflation. Everything on this page is an estimate and a projection, not advice.

Common questions

How many years will it take to reach financial independence?

This page solves the years-to-FI equation in closed form using the growth rate you actually keep: market return minus fund expense, advisory fee, and tax drag, deflated to real dollars. Spending is income times one minus your savings rate, and the FI number is spending divided by a chosen withdrawal rate. Because markets vary, the result is a p5, median, and p95 range built from 1928 to 2025 rolling real returns.

How much does a 1% fee delay financial independence?

The fee tornado on this page re-solves years-to-FI with each extra annual fee dragged off the market return, reporting the cost in years rather than basis points. Because fees compound against you for the whole accumulation, a flat-sounding one percent per year shows up as added years of work. The exact number depends on your savings rate and horizon, which is why the tool computes the delta from your own inputs.

Why does a higher savings rate shorten time to financial independence?

A higher savings rate cuts the time twice: you invest more each year and you need a smaller portfolio because you spend less. The page notes textbook anchors at a 5 percent constant real return and 4 percent withdrawal rate, where a 50 percent savings rate solves to roughly 17 years and 75 percent to roughly 7 years. Its closed-form engine reproduces these classic figures from your decomposed real return.

What safe withdrawal rate applies to early retirees with long horizons?

Longer horizons lower the sustainable rate. The page offers Morningstar 2026 presets at 90 percent success: 3.9 percent for 30 years, 3.5 percent for 35 years, and 3.3 percent for 40 years, alongside the classic 4 percent from Bengen and Trinity. It also notes that rates for 45 to 50 year horizons are not published, leaving the 40-year 3.3 percent as the estimate available for very long retirements. The withdrawal rate sets the divisor in your FI number.

Written by Chris Park · Updated 2026-07-22
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