Coast FI Calculator
When can you stop saving?
Coast FI is the threshold where your invested money is enough, even if you never add another krone, dollar, or rupee, that compounding alone gets you to full FI by your target age. The earlier, less terrifying milestone on the path.
Your Coast FI number at age 32
NOK 3,162,656
If you have this much invested today, you can stop adding to your portfolio entirely; compounding alone would take you to NOK 12,000,000 by age 67.
Current invested
NOK 750,000
Gap to Coast FI
NOK 2,412,656
Full FI number (at age 67)
NOK 12,000,000
23.7% of the way to Coast FI
Multi-account portfolios · Coast date projections · joint households
The Coast FI idea, briefly
Full FI is the number where your portfolio funds your expenses forever at a safe withdrawal rate. Coast FI is the number where today’s portfolio, compounded for the years between now and your target retirement age, will reach the full FI number on its own. Reach Coast FI and the math takes over: you can step back from saving without endangering the retirement plan, even if it doesn’t feel like you’ve arrived.
The formula is the inverse of compound growth. If your full FI number is F, your years to coast age is n, and your real (inflation-adjusted) annual return is r, then:
coastNumber = F / (1 + r)^n
This calculator uses the Fisher equation to convert your region’s nominal return assumption into a real return before doing the math, because the only return that matters for a multi-decade projection is the one that survives inflation. The regional defaults are the same ones fjordFIRE uses in-app, and you can override any of them.
Why Coast FI is the more useful milestone
Full FI is a long way away for most people in their 20s and 30s. Coast FI happens years earlier, often 10–15 years before, and it’s the moment your relationship to money changes. Career risk drops. The job is suddenly optional in a way it wasn’t the year before. You can take the sabbatical, switch to part-time, change industries, or just turn down the next promotion that would mostly come with more stress.
That doesn’t mean most people should stop saving at Coast FI. It means they could, and that’s the part that matters psychologically.
What this calculator deliberately doesn’t do
It treats your invested net worth as one number. In real life, locked retirement accounts (401k, IPS, PPF, pension) compound the same way but can’t be touched until access age, so their contribution to Coast FI is real, but their contribution to your day-to-day flexibility is zero until then. It also doesn’t model the sequence-of-returns risk that determines whether your real-world coast reaches the line.
The in-app version models locked vs accessible separately, projects per-account compound paths, and runs Monte Carlo so you see the probability fan around the coast number, not just a single deterministic line.
What the full version adds
- Separate Coast FI for accessible (active-FI) vs total (incl. locked retirement) net worth.
- Monte Carlo: 1,000 simulated futures showing the probability your coast delivers.
- Per-member Coast FI in two-person households.
- Recalculated monthly from your real numbers.
- Joins the rest of the picture: your FI date, your safety net, your destinations.
Waitlist open. Cohorts onboarding now; the next opens before public launch. We’ll be in touch within a week of signup. Join the waitlist →
Go deeper: Lesson: Coast / Barista / Lean / Fat FI →
More: FIRE Number calculator → · Relocation Runway calculator → · Read: Coast FI in Norway →
How we think about the numbers behind every figure: The method →
A calculator answers one question. fjordFIRE keeps the whole picture updated every month.