Compound Interest Calculator
Most people overestimate how much they need to start, and underestimate how much they lose by waiting. This shows how small, consistent habits turn into significant outcomes.
Logic Updated: April 2026
Compound Interest Calculator
Amount added to the investment every month.
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Why this logic matters
Compounding rewards time more than it rewards the size of your contribution. The same weekly amount, the same return, can end up wildly different depending only on when you start.
$50 a week at 7% grows to around $107,000 after 20 years. Leave it running for 30 years instead, same $50 a week, and it grows to around $245,000. Ten extra years more than doubles it.