Finance & money · Interest Savings
Interest Calculator
Calculate simple and compound interest on any principal. Choose compounding frequency (monthly, quarterly, annually) and see total amount plus interest earned.
How it works
Calculates simple and compound interest. Simple interest grows linearly on the principal. Compound interest earns interest on accumulated interest, growing exponentially.
Step by step
- 1Choose Simple or Compound interest type.
- 2Enter your principal, annual rate, and time in years.
- 3For compound interest, select how often interest is compounded.
- 4Simple: Amount = P × (1 + r × t). Compound: Amount = P × (1 + r/n)^(n×t).
Examples
Simple interest: 8% on $10,000 for 5 years
10,000 × (1 + 0.08 × 5) = 14,000. Interest = $4,000.
Inputs
- mode:
- 0
- principal:
- 10000
- rate:
- 8
- years:
- 5
- frequency:
- 1
Result
- amount:
- 14000
- interest:
- 4000
Compound monthly: 8% on $10,000 for 5 years
10,000 × (1 + 0.08/12)^60 ≈ 14,898.46.
Inputs
- mode:
- 1
- principal:
- 10000
- rate:
- 8
- years:
- 5
- frequency:
- 12
Result
- amount:
- 14898.46
- interest:
- 4898.46
Frequently asked questions
What is the difference between simple and compound interest?▾
Simple interest is calculated only on the original principal. Compound interest is calculated on the principal plus accumulated interest, so your money grows faster.
How does compounding frequency affect my returns?▾
More frequent compounding means slightly higher returns. Monthly compounding gives more than annual, and daily compounding gives the maximum for a given nominal rate.