Coast FIRE and Barista FIRE

Coast FIRE is the earliest age you could stop saving and still reach your target by retirement. Barista FIRE is the earliest age you could switch to part-time work and still get there. Both cards are on the FIRE page; Lean and Fat FIRE are only on the free calculator.

Updated Oct 17, 2026 · 3 min read · Works on desktop and mobile web

Where to find itFIRECoast FIRE

Both cards read off the same projection as your chart, so they use the same accounts, returns, savings and target. Click Details on either card for the working.

Coast FIRE

The idea: at some point your portfolio is big enough that, left alone, it will grow into your target by the time you retire. After that you only need to earn enough to cover your spending.

Coast number at an age = target at retirement ÷ (1 + r) ^ (retirement age − that age)

  • r is the average return of your included assets, weighted by their value (7% if there are none).
  • Retirement age is Your Retirement Age (default 65). It is used here even if Include Retirement Age is off. To change it, turn on Include Retirement Age in Assumptions so the stepper appears, set the age, and press Save. The age stays if you turn the toggle back off.
  • FIYR checks each year of your projection, with your current saving continuing, and shows the first age where the projected balance is at least that year's coast number.

Example: a $1,500,000 target, retirement at 65 and a 7% return. At 40, with 25 years to go, the coast number is $1,500,000 ÷ 1.07^25, about $276,000. The coast number rises every year you wait, because there is less time left to compound.

A card reading Age 41 with 6y, $0 contributions underneath means that six years from now you could stop contributing.

Barista FIRE

The idea: switch to lower-paid or part-time work, let the portfolio cover the gap between that income and your spending, and still arrive at your target by retirement age.

  • Part-time income defaults to $30,000 a year. Change it in the Barista Details window under Part-time income you'd earn, then press Save in Settings to keep it.
  • Part-time income rises with inflation each year.
  • Each year after the switch, the portfolio grows at r. If your part-time income is less than your spending, the shortfall is withdrawn and grossed up for your tax rate. If it is more, the extra is invested.
  • A switch age works only if the balance never hits zero and is at or above the target by your retirement age. The card shows the first age that works.
FIRE Target
$1,500,000
25x spending
Coast FIRE
Age 36
4y, $0 contributions
Barista FIRE
Age 41
9y @ $30,000/yr
Coast number at age 36: $1,500,000 ÷ (1 + 7%)29 = $210,844. Your projected portfolio passes it that year, so you could stop contributing and still reach the target by 65.
Try a different part-time income or retirement age and watch both cards move.

When a card says N/A or Unreachable

The Details window explains why. The messages are:

MessageWhat to do
Add your birthdate so we can put your plan on a timeline.Add your date of birth (FIRE asks for it, or set it in Settings).
Set your annual spending or a manual FIRE number first.Your target is $0. Open Summary, or set Custom Annual Spend or Custom FI Target.
You're already at or past your retirement age of N.Raise Your Retirement Age (turn on Include Retirement Age in Assumptions to see it).
On your current contributions and a X% portfolio return, you don't reach Coast FIRE before your retirement age of N.Coast FIRE only. The plan genuinely does not get there in time. Save more, push retirement later, or lower spending.
There's no age before N where dropping to $X/yr still gets you to your target...Barista FIRE only. Try a higher part-time income, a later retirement age, or a lower spending figure.

Lean FIRE and Fat FIRE

The FIRE page does not show Lean or Fat FIRE. The free FIRE calculator does: Lean is the FIRE number for 70% of your spending and Fat for 150%. In the app you can get the same effect by turning on Custom Annual Spend and typing a leaner or larger figure.

Common questions

What is the difference between Coast FIRE and Barista FIRE?

Coast FIRE assumes you stop contributing but still cover your own spending. Barista FIRE assumes you switch to part-time income and let the portfolio cover any shortfall, so it usually comes later.

Can I change the $30,000 part-time income?

Yes. Click Details on the Barista FIRE card, change Part-time income you'd earn, then press Save at the bottom of Settings.

Why does Coast FIRE use age 65 when I turned off Include Retirement Age?

Coast and Barista always measure against Your Retirement Age (65 by default). To change it, turn on Include Retirement Age in the Assumptions section, set the age, press Save, then turn the toggle off again if you only wanted it for Coast and Barista.

Where are Lean FIRE and Fat FIRE?

Only on the free FIRE calculator at fiyr.app/fire-calculator. In the app, use Custom Annual Spend to model a leaner or larger lifestyle.

Still stuck?

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