Coast FIRE Calculator
How Much Do You Need Invested Today to Stop Contributing and Still Retire?
Coast FIRE is the point where your current investments are large enough that compound growth alone can carry your portfolio to your full retirement target by your chosen age — even if you stop making new contributions.
In plain terms, Coast FIRE means your portfolio has reached escape velocity. You still need enough income to cover your current lifestyle, but you no longer need to keep aggressively investing for traditional retirement if your assumptions hold.
Your FIRE milestone
At your current pace, you could reach financial independence at age 64, in about 34 years, around 2060.
If your monthly spending dropped to $2,800 after a move, FIRE could move from age 64 to age 48 — about 16 years sooner.
How Coast FIRE actually works
Coast FIRE is based on present value. Instead of asking how much you need at retirement, it asks how much you need invested today so that compounding alone grows your portfolio to that future target.
The basic idea is: full future FIRE target ÷ expected compounded growth over the years remaining until retirement = Coast FIRE number today. Once your portfolio reaches that number, additional contributions become optional rather than required under the model.
What changes your Coast FIRE number most
Years until retirement
The more time compounding has to work, the smaller the Coast FIRE number you need today.
Investment return assumption
Small changes in expected return can shift the Coast FIRE number materially because the model depends heavily on long-term compounding.
Full FIRE target
Your Coast FIRE number depends on the full retirement number you eventually need, so higher expected retirement spending raises the target.
Living costs today
Once you hit Coast FIRE, you still need enough earned income to cover your current life until retirement actually begins.
Who Coast FIRE is usually best for
Coast FIRE is often attractive for people who want to reduce work pressure before reaching full traditional FIRE. It can be a strong fit for someone who wants flexibility, career optionality, or the ability to shift into lower-stress work while still letting investments compound in the background.
It is usually most useful for people who already have a meaningful investment base and enough time left before retirement for compounding to matter.
What this calculator includes — and what it does not
Included
- Coast FIRE milestone logic
- Portfolio growth projection
- Return-based target modeling
- Comparison against a future FIRE target
Not fully modeled
- Sequence-of-returns risk in detail
- Changing tax treatment over decades
- Every market-cycle scenario
- Your future spending changes with perfect precision
This tool is built for planning direction, not certainty. Coast FIRE is highly sensitive to long-term assumptions, so the output is most useful as a scenario-planning estimate.