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Savings Rate Calculator

Your savings rate is the single biggest lever you have. At 10%, you work 43 years. At 50%, under 17. Find out where you stand — and what happens when you push it higher.

Everything you spend: housing, food, transport, etc.
Brokerage, savings accounts, after-tax investments
Before-tax retirement contributions per month
7% = historical real return of index funds
Post-Tax Savings Rate
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True Savings Rate (incl. pre-tax)
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Implied FIRE Number
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Years to Financial Independence
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Age at Financial Independence
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Years Saved at +5% Savings Rate
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Years Saved at +10% Savings Rate
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Monthly Spending in Retirement
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Why Savings Rate is the Ultimate Lever

Every other financial decision — which fund to pick, whether to refinance, even your salary — matters far less than your savings rate. Why? Because savings rate determines both how fast your wealth grows and how much income you actually need in retirement. A higher savings rate compresses your timeline from both ends simultaneously.

Post-Tax Savings Rate = Monthly Savings ÷ Monthly Take-Home
True Savings Rate = (Savings + Pre-Tax Contribs) ÷ Gross Monthly Income
FIRE Number = Annual Expenses × 25
FI Years = log((FIRE + PMT/r) / (PV + PMT/r)) / log(1 + r)

The Famous "Years to FI" Table

The relationship between savings rate and years to financial independence is one of the most powerful ideas in personal finance. It was popularized by Mr. Money Mustache in 2012 and is derived from the 4% safe withdrawal rate and historical 7% real market returns:

  • 10% savings rate → ~43 years to FI
  • 20% savings rate → ~37 years to FI
  • 30% savings rate → ~28 years to FI
  • 40% savings rate → ~22 years to FI
  • 50% savings rate → ~17 years to FI
  • 60% savings rate → ~12 years to FI
  • 70% savings rate → ~8.5 years to FI
  • 80% savings rate → ~5.5 years to FI
What is a good savings rate?
The typical American saves 5-8% of income — which leads to a 40+ year working career. Most personal finance experts recommend at least 20%. FIRE-focused individuals typically target 40-70%. There is no single "right" answer — it depends on your goals and lifestyle priorities. But every 5% increase in savings rate typically shaves 2-5 years off your path to financial independence. Even getting from 10% to 20% cuts nearly 6 years from your timeline.
How does savings rate determine retirement age?
Savings rate works from both sides: saving more means your portfolio grows faster, but it also means you need less in retirement (since you're already living on less). At a 50% savings rate, you live on half your income — which means you only need 12.5× your annual savings invested to retire (at 4% SWR). The math compounds powerfully, which is why jumping from 10% to 50% cuts 26 years off your timeline, not just 40%.
What counts in savings rate — only post-tax savings or also 401k?
Your "true savings rate" should include all savings: post-tax savings, 401k/403b contributions, IRA contributions, HSA contributions, and any employer match (which is essentially free savings). Some people calculate savings rate relative to take-home pay (post-tax rate) and some relative to gross income (true rate). The take-home rate is simpler but understates your actual savings power. The gross/true rate is more accurate for FI planning since it captures all wealth accumulation.