Simple Interest Calculator
Enter the capital, rate, and time. There's no fixed unit: pick any period you like (day, month, year...) and use that same period for both the rate and the time — e.g. a 2% monthly rate with time in months.
Final amount: $1,240.00
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How it works
With simple interest, the interest amount is always calculated on the original capital, never folding in interest from prior periods — so growth is linear, not exponential. The formula is I = C × i × t, where C is the capital, i is the rate (as a decimal), and t is the time. The final amount is A = C + I. Use the rate and time in the same period unit (e.g. a "% per month" rate with time in months).
Frequently asked questions
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