Slow FIRE Calculator
Last verified · Methodology
Set a full-speed savings rate and a slower one against the same target, and see the trade in years and in dollars.
Two ways to reach the same number
Save less, and spend the difference on life now or work fewer hours.
Converts the money you free up into hours of work you could drop.
Real return used in the math: 3.88%
What slowing down costs
8.8 years
Full speed gets you to $1,375,000 at 51. Slow FI gets there at 59, and in exchange you keep $1,700 a month for life now, about 9.8 hours of work a week at your pay.
Money freed before full-speed FI
$379,100
Spent on life instead of saved
Price of each extra working year
$43,326
Lifestyle bought per year of delay
Both paths to $1,375,000
What Slow FI trades
Full-speed FIRE treats the working years as a cost to minimize. Slow FI treats them as years worth living well, and accepts a later finish in exchange. The calculator makes the trade concrete: the extra years on one side, the money you get to use now on the other.
In the default example, saving $3,500 a month reaches a $1.375 million target in about 18.6 years. Dropping to $1,800 a month takes about 27.3 years. Over the 18.6 years the fast path would have taken, the slower plan leaves about $379,000 in your hands, roughly $43,000 for each extra year worked.
Why cutting savings in half does not double the time
Your existing balance compounds no matter what you add. At 32 with $120,000 invested, that money alone grows substantially over two decades, and it carries both plans. The monthly contribution only has to close the remaining gap, so reducing it stretches the timeline far less than proportionally.
Three ways people use Slow FI
Spend on what matters now
Travel while it is easy, help family, or pay for experiences that do not wait until your fifties.
Work less
Convert the freed money into time: a four-day week, longer breaks between jobs, or a lower-paid role you prefer. The calculator converts the monthly difference into hours per week at your pay.
Reduce risk of burnout
A plan that requires extreme saving for twenty years is a plan many people abandon. A slower pace that you can keep up often finishes sooner than an aggressive one you quit.
The rest of the FIRE family
To set the target itself, use the FIRE number calculator. To see when you can stop contributing entirely, the Coast FIRE calculator finds that milestone. And if the goal is part-time work rather than a slower pace, the Barista FIRE calculator models it.
Slow FI, or Slow FIRE, is financial independence reached deliberately at a moderate pace. Instead of saving 50% to 70% of income to retire as early as possible, you save enough to stay on track and use the rest to enjoy life now, whether that means spending on things you value, working fewer hours, or taking time off between jobs.
Coast FIRE is a milestone: the point where your existing investments will grow to your target with no further contributions. Slow FI is a pace: you keep contributing, just less aggressively. Many people on a Slow FI path pass Coast FIRE along the way, at which point they can slow down further.
Barista FIRE means you have left full-time work and part-time income covers part of your spending while the portfolio covers the rest. Slow FI usually means you are still working and still saving, just at a lower rate. Slow FI can end in full FIRE, Barista FIRE, or a traditional retirement.
It depends on how far you cut savings and where you start. Halving monthly savings rarely doubles the time, because your existing balance keeps compounding regardless of what you add. In the default example, cutting savings by almost half adds about 8.8 years, not 18.
That is a values question, and the calculator puts a price on it. In the default example, every extra working year buys about $43,000 of money you spend on life before full-speed FI would have arrived. Whether that is worth a year of work depends on what you do with it and how much you like your job.