FIRE Date & Savings Rate Calculator

1. What you’ll see after you calculate

This calculator estimates your path to financial independence (FI) in today’s money. You’ll see your FI number (portfolio size needed to support your target spending), an estimated time to FI in years and months, and an approximate FI date on the calendar. The second column surfaces your key assumptions: target spend, SWR, expected real return, income, and savings rate. Everything is expressed in USD for clarity.

2. Which inputs move the FI date the most

Your target annual spend and SWR define the goal: lower spend or a lower withdrawal rate both change the FI number. Your savings rate and income combine into a monthly contribution, which drives how fast you close the gap between your current stash and the FI number. Finally, expected real return is the engine in the background: higher returns shorten the journey, but you should pick a conservative number that would still feel realistic if markets underperform for a decade.

3. How to interpret the timeline

The headline “Time to FI” is a smooth mathematical projection, not a promise. Markets are lumpy, so reality will wander above and below the line. Use the timeline as a planning anchor: if the estimate is 18 years and you want closer to 10, you now know how big that gap is and can work backwards by adjusting savings, spending, or return assumptions.

4. Real vs. nominal thinking

The calculator works in real terms—after inflation. That means both your FI number and your contributions are expressed in today’s purchasing power. This keeps your plan comparable across time: your “30,000 USD” target spend is implicitly “whatever buys the same lifestyle later”, rather than a fixed nominal figure that inflation eats away. If you use nominal returns, you’ll double-count inflation and get optimistic timelines.

5. Making your plan more realistic

For a robust plan, sanity-check three things: the size of your contribution relative to income, the level of your target spend compared with your current life, and whether your return assumption lines up with your actual asset mix. A globally diversified, low-cost portfolio may justify a mid-single-digit real return; concentrated or expensive portfolios may deserve less.

6. Practical knobs you can turn

If FI feels too far away, start with three simple adjustments: raise your savings rate by a few percentage points, trim one recurring expense category to permanently lower target spend, and review fees and asset allocation. Even modest improvements in each area can pull the FI date forward by years over a long horizon.

7. When to revisit the numbers

Treat the output as a living snapshot. Recalculate after major life events: a job change, moving cities, paying off a mortgage, having children, or significantly changing your investment strategy. Over time, the value is not in a perfect forecast but in continuously aligning your savings behavior with the lifestyle you ultimately want.

1. FI number = Target annual spend ÷ SWR. For example, 30,000 USD ÷ 0.04 = 750,000 USD.

2. We convert your expected real return r (per year) into a monthly rate rₘ = (1 + r)^(1/12) − 1, then apply it to your current stash every month, adding the monthly contribution at the end of each step.

3. Monthly contribution = (Take-home income × Savings rate) ÷ 12. The projection iterates month by month until the portfolio balance reaches or exceeds the FI number, or 1,200 months (100 years), whichever comes first.

4. If the model doesn’t reach FI within 100 years with your inputs, we flag it as “not reached” in the summary. In that case, raising savings, lowering target spend, or picking a more realistic return assumption will usually bring the plan back into a feasible range.

This simplified model ignores volatility, taxes, and changing contributions. Use it as a planning compass and pair it with more detailed modeling or professional advice before making major decisions.