Sinking Fund Calculator
Spreads a known future cost into a monthly amount.
Set aside each month
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Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
Total you will pay in —
Interest earned —
The formula
monthly = (cost − existing grown) ÷ ((1 + i)^n − 1) × i
It works like a savings goal, but for a cost you know is coming, such as a new roof or car. i is the annual interest ÷ 12, and n the number of months.
What to watch out for
Run one for each large known cost, so that it never lands as a surprise.
Frequently Asked Questions
What is a sinking fund?
Money set aside over time for a specific expected cost. Unlike an emergency fund, you plan to spend it.