Round-up calculator
Estimate the spare change from rounding up card purchases, invested over the years.
Spare change after 10 years
Round-ups move about $32.50 a month without you noticing. Check the app's monthly fee: on small balances it can eat most of the growth.
How this calculator works
Round-up apps round each card purchase to the next dollar and invest the difference. The average round-up is about $0.50.
The calculator turns your purchases into a monthly amount and grows it at your chosen return.
Common questions
Are round-ups worth it?
They help build a habit, but the amounts are small. Compare any monthly app fee with what you invest: a $3 fee on $30 a month is a 10% cost.
Can I boost round-ups?
Many apps offer 2× or 3× multipliers, or let you add a recurring deposit.
Where does the money go?
Usually into a diversified portfolio of ETFs chosen by the app.
FatDCA calculators are educational estimates, not investment, tax or legal advice. Results depend on the assumptions you enter, and past returns do not predict future returns.
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