What is Barista FIRE
Semi-retirement: withdrawals plus a part-time income cover spending. You leave full-time work, but some earned income is still in the plan. On the defaults, $60,000 of spending minus $25,000 of part-time income is $35,000 a year — $875,000 at 4%, plus the healthcare bridge. Coast FIRE on the same $60,000 spend is the full $1,500,000 discounted back, with no draw until retirement: the Coast FIRE calculator. Healthcare until Medicare is usually the extra bill — that is why this barista FIRE calculator has a premium field. Lean and Fat FIRE are the full-independence numbers on the same scale: Lean and Fat.
The calculator
$60,000 of spending minus $25,000 of part-time income is $35,000 a year, which at 4.0% needs $875,000 plus $133,421 for the healthcare bridge, $1,008,421 in total. Full FIRE without that income is $1,500,000.
How it works
Barista FIRE is the 4% (or other) rule applied to the gap, not to full spending. Coast FIRE is the cousin that keeps working full-time and stops contributing; this one drops to part-time and starts drawing. Healthcare is the present value of net ACA (or other) premiums from the semi-retire age to Medicare, added on top of that capitalised gap. The Barista FIRE health-insurance guide is the long form; the Coast FIRE calculator is the cousin that keeps working full-time.
Assumptions
Part-time income is treated as reliable and pre-tax. Healthcare is the net premium after any subsidy, not the sticker price. If that job or that subsidy disappears, you need the full FIRE number. One real return, no fees.