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Savings Rate Calculator

Enter your income and expenses to get your savings rate, FI number, and years to financial independence — plus a sensitivity table showing how each 5% increase cuts years off your timeline.

401(k) Limit 2024$23,000
Roth IRA Limit$7,000
S&P 500 Avg Return~10%/yr

Income & Savings

Annual Take-Home

Timeline

On track — 26.7% net savings rate. FI in 24 years. Keep compounding.

Gross Savings Rate20.0%savings / gross income
Net Savings Rate26.7%savings / take-home
Effective Rate20.0%no match entered
Net Savings Rate
26.7%
Good · 20–35%

Solid foundation. FI in 25–35 years at this rate.

$20,000/yr saved · $55,000/yr expenses

FI Progress
3.3%
$45K today$1.4M FI target (25× expenses)

$1.3M remaining · 23.9 years at current pace

FI Number

$1.4M

25× annual expenses

Years to FI

23.9

Year 2050

At Retirement

$2.8M

Age 65

5% SR Boost Saves

2.6 yrs

off FI timeline

Coast FI

Stop contributing at age 39

At $20K/yr saved, your balance will hit the Coast FI target ($147K) at age 39 — then grow to $1.4M by 65 at 7%/yr with no further contributions.

Saving an extra 5% ($3,750/yr more → $23,750/yr total) cuts your FI timeline by 2.6 years. That's the most powerful lever on this page.

Years to FI by Savings Rate

RateAnnual SavingsYears to FI
5%$3,75043.2
10%$7,50036.5
15%$11,25031.7
20%$15,00027.9
25%← you$18,75024.8
30%$22,50022.1
35%$26,25019.7
40%$30,00017.6
50%$37,50013.8
60%$45,00010.4
70%$52,5007.4
1

Step 1 — Gross annual income

grossIncome = all income before taxes

= $100,000

= $100,000

Self-employed: use your 2-year average Schedule C net income for lender-comparable income, or gross revenue for your own planning. W-2: this is your total wages including any pre-tax 401k contributions.

2

Step 2 — Estimated taxes → net take-home

netIncome = grossIncome − taxes

$100,000 − $25,000 taxes

= $75,000/yr net

Uses your entered take-home figure. 1099 workers: your effective rate should include estimated quarterly tax payments already set aside.

3

Step 3 — Total savings & annual expenses

totalSavings = 401k/IRA + taxable | annualExpenses = netIncome − totalSavings

savings: $20,000 | expenses: $75,000 − $20,000 = $55,000

= $20,000/yr saved · $55,000/yr spent

Annual expenses = net income − all savings. This becomes the denominator of your FI number (expenses × 25). Lowering expenses has a double effect: saves more AND reduces the FI target.

4

Step 4 — Net savings rate

netSavingsRate = totalSavings / netIncome

= $20,000 / $75,000

= 26.7% — Good (20–35%)

Net rate uses take-home as denominator — what % of spendable income you're saving. FI researchers (MMM, FIRE community) typically cite net savings rate for FI timeline comparisons.

5

Step 5 — Gross savings rate

grossSavingsRate = totalSavings / grossIncome

= $20,000 / $100,000

= 20.0%

Gross rate is better for comparing across income levels (no ambiguity about tax treatment). It's also the rate used to estimate minimum savings rate needed for retirement by a target age.

6

Step 6 — Effective rate with employer match

effectiveSavingsRate = (totalSavings + employerMatch) / grossIncome

No employer match entered

= 20.0% (no match entered)

Enter employer match above to see effective rate. A typical 4% match on $100k salary = $4,000/yr in free contributions.

7

Step 7 — FI Number (25× rule / 4% safe withdrawal)

fiNumber = annualExpenses × 25 = annualExpenses / 0.04

= $55,000 × 25

= $1.4M

William Bengen (1994) found 4% is the maximum sustainable withdrawal rate across all 30-year historical periods. The Trinity Study (1998) confirmed 95%+ success rates. Your FI number is the portfolio where a 4% draw covers your expenses indefinitely.

Bengen 1994 · Trinity Study 1998

8

Step 8 — Years to FI (Shockingly Simple Math)

n = ln((FI + PMT/r) / (PV + PMT/r)) / ln(1+r) [r = 7% real return]

PV = $45K, PMT = $20K/yr, FI = $1.4M, r = 0.07

= 23.9 years → FI year 2050

7% real return assumes ~10% nominal stock market return minus ~3% inflation (historical US equities average). The PMT/r term is the "perpetuity value" of your annual savings stream. This is the formula from the MMM "Shockingly Simple Math" post generalized for a starting balance.

MMM 2012 · Bengen 1994

9

Step 9 — Coast FI number

coastFI = fiNumber / (1 + r)^yearsToTarget

$1.4M / (1.07)^23.9 = $147K

= $147K — you need $102K more

Coast FI is the balance that will compound to your FI Number by retirement (age 65) at 7%/yr — even if you stop contributing today. At age 39, your contributions become optional.

10

Step 10 — FI Progress milestones

milestone = fiNumber × pct% | progress = currentBalance / fiNumber

$45K / $1.4M = 3.3%

= 3.3% of the way to FI

25% = $344K ($299K away) | 50% = $688K ($643K away) | 75% = $1.0M ($986K away) | 100% = $1.4M ($1.3M away)

11

Step 11 — Impact of saving 5% more

newSavings = netIncome × (netSavingsRate + 5%) | ΔYears = yearsToFI_current − yearsToFI_new

new savings: $23,750/yr (+$3,750/yr) → FI in 21.3 years

= Saves 2.6 years off your FI timeline

A 5-percentage-point boost in savings rate at your income level means $3,750/yr more invested. This is the single most powerful lever on this page — more impactful than increasing investment returns by 1%.

12

Step 12 — Minimum savings rate to retire by target age & Rule of 72

minRate = solve(yearsToFI(rate, PV, expenses) ≤ yearsLeft) | doublingTime = 72 / returnRate%

yearsLeft = 33yrs | doublingTime at 7% = 10.3 years

= Your current 20.0% gross rate meets the target retirement age 65 threshold (minimum: 8.0%)

Rule of 72: at 7% real return, your portfolio doubles every 10.3 years. Your current $45K doubles to $90K by 2036.

Key insight

Net savings rate 26.7%, gross 20.0%. FI number: $1.4M — you're 3% there. Coast FI at age 39.

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