Compound Interest Calculator With Weekly Deposits

Compound Interest Formula:

\[ A = P \times (1 + R / 52)^{(52 \times T)} + C \times \frac{(1 + R / 52)^{(52 \times T)} - 1}{R / 52} \]

Principal (P):

Annual Interest Rate (R):

Time (T):

years

Weekly Deposit (C):

Final Amount (A):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Compound Interest Formula?

The compound interest formula with weekly deposits calculates the future value of an investment that earns interest compounded weekly, with regular weekly contributions. It accounts for both the initial principal and additional deposits.

2. How Does the Calculator Work?

The calculator uses the compound interest formula:

\[ A = P \times (1 + R / 52)^{(52 \times T)} + C \times \frac{(1 + R / 52)^{(52 \times T)} - 1}{R / 52} \]

Where:

$ A $ — Final amount ($)
$ P $ — Principal amount ($)
$ R $ — Annual interest rate (decimal)
$ T $ — Time in years
$ C $ — Weekly deposit amount ($)

Explanation: The formula calculates the compound growth of both the initial investment and regular weekly contributions, compounded weekly.

3. Importance of Compound Interest Calculation

Details: Understanding compound interest helps in financial planning, investment decisions, and retirement savings. It demonstrates how regular contributions can significantly grow wealth over time.

4. Using the Calculator

Tips: Enter principal amount in dollars, annual interest rate as a percentage, time in years, and weekly deposit amount. All values must be non-negative.

5. Frequently Asked Questions (FAQ)

Q1: What if the interest rate is 0%?
A: The formula simplifies to A = P + C × (52 × T), as there's no compounding effect.

Q2: How often is interest compounded?
A: This calculator compounds interest weekly (52 times per year).

Q3: Are weekly deposits required?
A: No, you can set C = 0 to calculate compound interest without additional deposits.

Q4: Can I use this for different compounding frequencies?
A: This specific calculator is designed for weekly compounding. Other frequencies require different formulas.

Q5: How accurate is this calculation?
A: The calculation is mathematically precise, assuming constant interest rate and regular deposits.