Free Simple Interest Calculator

Calculate simple interest on loans or investments. Find the interest amount and total value using principal, rate, and time.

USD
%
years

Total Interest

$1,500.00

Total Value$11,500.00

Total Interest vs Time Period

How to Calculate Simple Interest

Simple interest is calculated only on the original principal amount.

Formula

I = P * r * t

Where:

  • I = Interest
  • P = Principal
  • r = Annual rate (as decimal)
  • t = Time in years
  • Example Calculation

    You deposit $10,000 at 5% simple interest for 3 years.

    1. 01Interest = $10,000 * 0.05 * 3 = $1,500
    2. 02Total value = $10,000 + $1,500 = $11,500

    Example Calculations

    How much interest on $5,000 at 8% for 3 years?

    $1,200
    1. 1.Principal (P): $5,000
    2. 2.Rate (r): 8% = 0.08
    3. 3.Time (t): 3 years
    4. 4.Interest = P × r × t = 5,000 × 0.08 × 3 = $1,200

    How much interest on $10,000 at 5% for 2 years?

    $1,000
    1. 1.Principal: $10,000
    2. 2.Rate: 5% = 0.05
    3. 3.Time: 2 years
    4. 4.Interest = 10,000 × 0.05 × 2 = $1,000

    How much interest on $20,000 at 4% for 5 years?

    $4,000
    1. 1.Principal: $20,000
    2. 2.Rate: 4% = 0.04
    3. 3.Time: 5 years
    4. 4.Interest = 20,000 × 0.04 × 5 = $4,000
    5. 5.Total amount: $20,000 + $4,000 = $24,000

    Frequently Asked Questions

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