Coast FIRE Calculator
Find the number where your investments can finish the job without another dollar from you. Coast FIRE means you’ve invested enough that compound growth alone reaches your retirement number on time — every paycheck after that is yours to live on, travel on, or downshift with. For the exact formula behind this calculator, see how to calculate your Coast FIRE number.
Educational tool, not financial advice. This calculator runs a simplified projection on the numbers you enter, using assumptions — a fixed yearly return, steady inflation, the 4% rule — that no real market follows. The output is an estimate, not a plan, and not a recommendation tailored to your income, taxes, or risk tolerance. Her Own Compass is not a licensed financial advisor; before you act on a retirement or investing decision, talk to a licensed, preferably fee-only professional. Read the full disclaimer.
Run your numbers
Quick fills:
Your Coast FIRE number today
What the numbers mean
Coast FIRE number
The amount that, invested today, grows into your full retirement number by your retirement age with zero new contributions — calculated with your real (after-inflation) return.
Full retirement number
Your yearly retirement spending × 25 — the classic 4% rule. Spend $45,000 a year and the target is $1,125,000 in today’s dollars.
Per month to coast
What you’d invest monthly from now until retirement to close the gap. Watch it shrink every time your invested balance grows.
This calculator is education, not personalized financial advice — assumptions (returns, inflation, the 4% rule) are simplifications, and big decisions deserve a licensed professional. See our disclaimer.
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Investing for beginners
Index funds, retirement accounts, and the first $100 — explained without the finance-bro act.
Learn the basics →Budgeting on one income
Find the monthly investing money inside one paycheck — without giving up everything fun.
Free up cash →Travel Fund Calculator
Coasting is the long game — the travel fund is the short one. Run both numbers and live on purpose.
Fund the next trip →