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Coast FIRE Number by Age

How much you need invested at each age so compounding alone carries you to retirement. Get your number below, then see the full reference grid.

Your Coast FIRE number by age

Based on your inputs above, notice how much less you need the earlier you start:

If you're this age…You need invested todayYears to grow

Coast FIRE reference grid

The amount you need invested today to coast to different FIRE targets by age 65, assuming a 4% real (after-inflation) return, the same default as the calculator above. Find your age and target lifestyle.

FIRE targets shown assume the 4% rule (spending × 25): $750k ≈ $30k/yr, $1M ≈ $40k/yr, $1.5M ≈ $60k/yr, $2M ≈ $80k/yr.

Why your Coast FIRE number rises with age

Compound growth is exponential, so time is the most powerful input. A dollar invested at 25 has 40 years to grow; at 45 it has only 20. That's why someone at 25 might need only ~$140k to coast to $1M, while someone at 45 needs ~$375k for the same target. The lesson isn't "it's too late", it's that every year earlier dramatically lowers the bar.

Reached your Coast FIRE number? You can stop saving for retirement and let it grow. Not there yet? The Coast FIRE calculator shows exactly how much more you need.

Track your number as it grows

The FIRE Planning Toolkit includes a net-worth tracker and by-age Coast FIRE grid you can customise.

See the Toolkit, $20

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