Simple Interest Calculator
Calculate simple interest (I = P×r×t), total amount, and monthly schedule — free browser tool
Loan / Savings Details
Interest Earned
$1,500.00
I = P × r × t
Total Amount
$11,500.00
Principal + Interest
Total Return
15.00%
Over 36 months
Formula Breakdown
I = P × r × t
I = $10,000.00 × 5% × 3.0000 years
I = $1,500.00
Total = $10,000.00 + $1,500.00 = $11,500.00
Monthly Interest Schedule
| Month | Cumulative Interest | Total Balance |
|---|---|---|
| 1 | $41.67 | $10,041.67 |
| 2 | $83.33 | $10,083.33 |
| 3 | $125.00 | $10,125.00 |
| 4 | $166.67 | $10,166.67 |
| 5 | $208.33 | $10,208.33 |
| 6 | $250.00 | $10,250.00 |
| 7 | $291.67 | $10,291.67 |
| 8 | $333.33 | $10,333.33 |
| 9 | $375.00 | $10,375.00 |
| 10 | $416.67 | $10,416.67 |
| 11 | $458.33 | $10,458.33 |
| 12 | $500.00 | $10,500.00 |
| 13 | $541.67 | $10,541.67 |
| 14 | $583.33 | $10,583.33 |
| 15 | $625.00 | $10,625.00 |
| 16 | $666.67 | $10,666.67 |
| 17 | $708.33 | $10,708.33 |
| 18 | $750.00 | $10,750.00 |
| 19 | $791.67 | $10,791.67 |
| 20 | $833.33 | $10,833.33 |
| 21 | $875.00 | $10,875.00 |
| 22 | $916.67 | $10,916.67 |
| 23 | $958.33 | $10,958.33 |
| 24 | $1,000.00 | $11,000.00 |
| 25 | $1,041.67 | $11,041.67 |
| 26 | $1,083.33 | $11,083.33 |
| 27 | $1,125.00 | $11,125.00 |
| 28 | $1,166.67 | $11,166.67 |
| 29 | $1,208.33 | $11,208.33 |
| 30 | $1,250.00 | $11,250.00 |
| 31 | $1,291.67 | $11,291.67 |
| 32 | $1,333.33 | $11,333.33 |
| 33 | $1,375.00 | $11,375.00 |
| 34 | $1,416.67 | $11,416.67 |
| 35 | $1,458.33 | $11,458.33 |
| 36 | $1,500.00 | $11,500.00 |
Simple vs Compound Interest
| Feature | Simple Interest | Compound Interest |
|---|---|---|
| Formula | I = P × r × t | A = P × (1 + r/n)^(nt) |
| Interest grows on | Principal only | Principal + accrued interest |
| Common uses | Short-term loans, car loans | Savings accounts, mortgages |
| Result for same inputs | Lower interest | Higher interest over time |
Frequently asked questions
What does Simple Interest Calculator do?
Calculate simple interest (I = P×r×t), total amount, and monthly schedule — free browser tool
What should I check in the result?
Check units, rates, dates and assumptions. Compare a simple case by hand before using the result for a decision.