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Simple Interest Calculator

Calculate simple interest, total amount, principal, rate or time for loans and investments

₹
Initial amount (loan or investment)
%
Interest rate per year
Duration of loan or investment
💡 Quick Examples:
📚 Simple Interest Formula

SI = (P × R × T) / 100

Where: P = Principal, R = Rate, T = Time

Total Amount: A = P + SI

To find Principal: P = (SI × 100) / (R × T)

To find Rate: R = (SI × 100) / (P × T)

To find Time: T = (SI × 100) / (P × R)

Simple Interest vs Compound Interest

💰 Simple Interest

  • ✅ Linear Growth: Interest stays constant
  • ✅ Easy Calculation: Simple formula
  • ✅ Predictable: Fixed interest amount
  • ❌ Lower Returns: No compounding effect
  • 🔵 Use Cases: Short-term loans, simple investments

📈 Compound Interest

  • ✅ Exponential Growth: Interest on interest
  • ✅ Higher Returns: Compounding effect
  • ✅ Long-term Wealth: Best for investments
  • ❌ Complex Calculation: Advanced formula
  • 🟢 Use Cases: Investments, savings accounts

🏦 Common Applications

Personal Loans: Often simple interest

Car Loans: Usually simple interest

Bank FDs: Compound interest quarterly

PPF/EPF: Compound interest annually

Credit Cards: Compound interest monthly

💡 Key Insights

  • 📊 Short-term: Difference is minimal
  • ⏰ Long-term: Compound wins significantly
  • 💸 Loans: Simple interest is borrower-friendly
  • 💰 Investments: Compound interest is investor-friendly
  • 🎯 Planning: Choose based on your goal