Simple Interest Calculator
Interest earned only on the original principal — no compounding. Common for short-term loans, treasury bills, and bonds.
Results
Final balance (simple)
$0.00
Interest earned
$0
Compound equivalent
$0
Compounding bonus
$0
Simple interest growth
Compound (monthly) for comparison
The formula
A = P (1 + r · t)
where P is principal, r the annual rate (as decimal), and t the time in years. Interest earned = P · r · t.
When you'll encounter simple interest
Most consumer products use compound interest. Simple interest still appears in: most US auto loans (interest computed daily on the current balance, but not capitalized), short-term notes, treasury bills, and many business invoices ("Net 30 with 1.5% monthly thereafter").