Built for the FI/RE community

Retire decades earlier.
Know exactly when.

The only FIRE planning platform that tests your strategy against 155 years of real market history.

155
Years of data
6
Factor strategies
Scenarios tested
firewealthos.com / dashboard
FIRE date
2041
14 yrs from today
Survival rate
94.2%
@ 3.5% withdrawal
Best factor
HML + SMB
vs market only
Real portfolio paths · 1871–2026155 years
18711929197320082026

The honest truth

Most retirement calculators lie to you.

They use average returns — a single smooth line that never existed in real life. Real markets don't move in averages. They crash in 1929, stagnate through the 70s, boom in the 90s, and panic in 2008.

We test your strategy against every historical market crash, bull run and crisis from 1871 to today. If your plan would have survived the worst the market has thrown at investors over 155 years, you can sleep at night.

1929
Great Depression
1973
Stagflation
2008
Financial Crisis

What's inside

Built on the data the academics use.

Same datasets that power peer-reviewed retirement research — packaged into a planner you can actually run in 60 seconds.

155 years of data

Robert Shiller's monthly S&P series since 1871, paired with Ken French's full factor library. Real returns, real inflation, real dividends.

Factor investing

Test SMB, HML, Momentum, Quality, Profitability, and Investment factor tilts. See which strategy actually shortens your FIRE date.

Real purchasing power

Every projection is inflation-adjusted. Your £1m in 2050 is shown in today's money — so you know what your retirement actually buys.

How it works

From a vague goal to a real date in three steps.

  1. Step 1

    Set your numbers

    Income, savings rate, current portfolio, and target lifestyle. Two minutes, no signup required to play.

  2. Step 2

    Test your strategy

    Run your plan through every historical sequence since 1871. Toggle factors, withdrawal rates, fees and tax wrappers.

  3. Step 3

    Find your FIRE date

    Get a clear answer: the year you can retire with 95%+ historical survival — and what to change if you want it sooner.

Pricing

Start free. Upgrade when you're ready.

Built for serious FIRE planners. Cancel any time, your simulations stay yours.

Beta programme

Join as a founding user

First 10 users get £10 / $10 paid via PayPal and full premium access free, in exchange for using the product and giving us honest feedback.

See beta details

Free

£0forever

Get a feel for FIRE planning with the core calculator.

  • Basic FIRE number calculator
  • Single withdrawal rate test (4% only)
  • Pure market simulation only
  • 50 year horizon only
Start free

No credit card required

Most popular

Premium

£9.99/month · or £79/year
US: $12.99/month · $99/year

Everything in Free, plus the tools serious investors need.

  • Full factor comparison (all 6 strategies)
  • Withdrawal rates 0.5% to 20%
  • Global data toggle (MSCI World)
  • Fee and tax modelling (UK ISA/GIA/SIPP, US Roth/401k)
  • Robustness testing across all horizons
  • AI personalised guide (powered by Claude)
  • Save and revisit simulations
  • All retirement horizons 20–90 years
Go premium
Compare features
Free
Premium
Basic FIRE number calculator
Single withdrawal rate test (4% only)
Pure market simulation only
50 year horizon only
Full factor comparison (all 6 strategies)
Withdrawal rates 0.5% to 20%
Global data toggle (MSCI World)
Fee and tax modelling (UK ISA/GIA/SIPP, US Roth/401k)
Robustness testing across all horizons
AI personalised guide (powered by Claude)
Save and revisit simulations
All retirement horizons 20–90 years
Cancel any time
No card required
14-day money back