Flamingo FIRE Calculator

What is Flamingo FIRE?

Flamingo FIRE means saving half of your FIRE number, then leaving full-time work and saving nothing more: part-time or lower-paid work covers your living costs while the half grows into the full number on its own. The idea comes from Mrs. Flamingo at Money Flamingo, who calls it Flamingo FI because it’s FIRE standing on one leg.

In her version you stop adding to the portfolio once you reach half, and you don’t take anything out either. Your work pays the bills until the portfolio has doubled, which she expects to take roughly 10 to 15 years. After that you’re fully financially independent and can quit for good.

How the calculator works

It does two things. First it finds the age you reach half of your FIRE number, using the same month-by-month model as the FIRE calculator. Then it stops your contributions and works out how long the half takes to double.

FIRE number     = yearly spending ÷ withdrawal rate
flamingo number = FIRE number ÷ 2
real return     = (1 + expected return) ÷ (1 + inflation) − 1

Saving phase:  every month, balance = balance × (1 + real return)^(1/12) + contribution
               flamingo age = the first month balance ≥ flamingo number
Coasting phase: no contributions, no withdrawals
               years to full FIRE = ln 2 ÷ ln(1 + real return)

The doubling time depends on nothing but the real return. Your spending, your balance and your age don’t enter into it. If the real return is zero or negative, the half never doubles, and the calculator says so.

A worked example

Ravi is 32, has $120,000 invested and saves $3,000 a month. He spends $60,000 a year, so at 4% his FIRE number is $1,500,000 and his flamingo number is $750,000.

With 7% returns and 3% inflation, he reaches the half at 45. Then he stops saving. At a real return of 3.88%, the portfolio takes another 18.1 years to reach $1,500,000, so he’s fully independent at 63.

If he kept saving $3,000 a month the whole way, he’d hit $1,500,000 at 54. Flamingo gets him out of full-time work 9 years sooner, and in exchange full independence arrives 9 years later. Whether that’s a good deal depends on how much he dislikes his job.

Why does the doubling take longer here than on Money Flamingo?

Because the assumptions differ. Money Flamingo’s math post hopes for a 7% return after inflation and considers 5% realistic for her own family’s investments. Using the rule of 72, she puts those at around 10 and 15 years to full independence. This site’s defaults are a 7% return and 3% inflation, which is only 3.88% after inflation.

At a 7% real return, Ravi would go flamingo at 43 and be done at 53. That’s the version that makes the idea look easy. I’d plan with the lower number and treat anything better as a bonus, because 7% after inflation, year after year, is an optimistic thing to count on for a whole portfolio.

Flamingo FIRE vs Coast FIRE

Flamingo FIRE is basically Coast FIRE with the retirement age picked for you. Coast FIRE asks when you want to retire and tells you the balance that grows into your full number by then. Flamingo FIRE fixes the balance at half, which quietly sets your retirement age at one doubling time after you stop saving.

You can see it in Ravi’s numbers. Coast FIRE with a retirement age of 62 puts his stopping point within 4 months of his flamingo age. They’re the same plan. What changes things is picking a different retirement age:

If Ravi would be happy fully retiring at 65, Coast FIRE lets him stop saving at 42, earlier than flamingo. If he wants out by 60, he needs to save until 46. Flamingo lands in between.

The weakness of the half rule is that it ignores your age. Someone who is 45 with $300,000 and the same saving and spending as Ravi reaches the half at 54 and the full number at 72, which isn’t early retirement at all. The strength is that it’s easy to remember. If you’d rather choose the age yourself, the Coast FIRE calculator does that.

What does your job have to cover?

All of it. In the plan as Money Flamingo describes it, the portfolio isn’t touched until it doubles, so Ravi’s work has to pay $60,000 a year after tax for about 18 years. That’s roughly $1,086,419 in today’s dollars. “Semi-retired” can still mean a real job.

If your work pays less than you spend, you’ll pull from the portfolio and the doubling slows. At that point you’re closer to Barista FIRE, where the portfolio covers part of your spending from the start. The Barista FIRE calculator handles that case.

Two practical things help flamingo. Because Ravi doesn’t touch his investments until 63, the 10% additional tax on retirement account withdrawals before 59½ never comes up. Health insurance is the harder part, since many part-time jobs don’t come with it. The health insurance before 65 guide covers the options.

What the calculator leaves out

It assumes the same return every year. A crash just after you stop saving won’t wreck the plan, since you’re not withdrawing, but it can push the full number back several years. It also leaves out taxes, Social Security and any growth in your spending. If your plan only works with every assumption going your way, save a bit past half before you ease off.