FIRE Calculator

When I started planning my own FIRE journey, the first thing I needed was a clear answer to "how many years away am I?" — not the abstract version that US-focused calculators give, but the European-resident version that accounts for tax during withdrawal and EUR-denominated portfolios.

The calculator above is exactly that. Set your inputs to your situation and see the answer.

How to use this

The calculator does the math for you, but the inputs deserve some thought.

Annual after-tax spending: this is the amount you'd need each year to maintain your lifestyle, after tax. Be honest. Most people underestimate by 20-40% when they guess; the right answer comes from looking at the past 12 months of bank statements.

Effective tax rate on investment income: 25-30% for most EU countries (Abgeltungsteuer in Germany, prélèvement forfaitaire in France, etc.). Lower for UK ISA-wrapped portfolios (set to 0% if your portfolio is fully ISA-sheltered). Lower for French PEA-wrapped portfolios after the 5-year holding period.

Real return assumption: 5% (after inflation) is the conservative European-suitable default. 6-7% real is the historical US average. 4% is a more conservative assumption that matches the post-2022 view of forward returns.

Safe withdrawal rate: 3.5% is the consensus for early retirement (40+ year horizons). 4% works for traditional retirement (30-year horizons). Use 3.0-3.3% if you're risk-averse or have very long horizons (50+ years).

Monthly savings: be honest about what you can actually sustain, not what you'd like to. Sustained 30% savings rate beats aspirational 50% that lapses after a year.

What the result tells you

The calculator returns three key numbers:

Your FI number: how much portfolio you need to be financially independent at your current spending level. This is the goal post.

Years to FI: how long it takes to reach the FI number with your current trajectory. If this is shorter than your years-to-target-retirement-age, you're on track. If longer, you need to adjust either savings rate, spending target, or timeline.

Portfolio at target retirement age: where your portfolio actually lands at the age you'd like to retire. The gap (or surplus) vs your FI number tells you whether the target age is realistic.

Common scenarios this surfaces

A few patterns the calculator typically reveals:

The "tax was the missing variable" scenario: investors using copy-pasted US 4% rule math without tax adjustment typically see their FI number jump by 30-40% when they add the European tax adjustment. The portfolio they thought was "almost there" is actually 4-5 years further away.

The "I need to save more" scenario: investors targeting €40K/year spending at €1,000/month savings rate typically see FI is 30+ years away, which is past traditional retirement age. The remediation is either lower spending target or higher savings rate.

The "I'm closer than I thought" scenario: investors with €100K-€200K already invested who haven't run the math typically see FI is achievable in 12-18 years rather than the "decades away" they assumed. Compounding does most of the work once you have a meaningful base.

The "I should consider Coast FIRE" scenario: investors approaching their 40s with significant existing investments often see they're already at Coast FIRE — meaning they could stop saving and let compounding finish the job. The Coast FIRE Calculator is the right tool for that variant.

The next steps

Once you've run the calculator and understand your numbers:

1. If FI is achievable in 15-25 years at current trajectory: stay the course. Set up monthly automation through Trade Republic and DEGIRO, maintain savings discipline, audit annually.

2. If FI is 25+ years away: increase savings rate or reduce spending target. Even 5 percentage points of savings rate (from 30% to 35%) typically shaves 4-6 years off the timeline.

3. If FI is achievable in under 10 years: re-validate your spending target. Most people who hit FI in single-digit years had high incomes and modest lifestyles; verify your numbers are realistic.

4. If the math doesn't add up no matter what: consider Coast FIRE as a more achievable target. Reaching Coast FIRE is typically 10-15 years from zero on disciplined saving and provides career flexibility without the extreme savings discipline full FIRE requires.

For the full conceptual framework, see the FIRE movement guide. For the practical roadmap to actually execute, how to retire early in Europe. For the technical foundations, the 4 percent rule and sequence of returns risk.