Compound Interest Savings Calculator
This calculator helps you understand how your savings can grow over time with the power of compound interest, even when you make regular contributions. It combines your initial investment with periodic deposits to project your future wealth.
Your initial lump sum investment.
The yearly interest rate as a percentage.
The amount you add periodically.
How often you make contributions.
How often interest is calculated and added to the principal.
The total investment period.
This calculator helps you understand how your savings can grow over time with the power of compound interest, even when you make regular contributions. It combines your initial investment with periodic deposits to project your future wealth.
Future Value (FV) = P(1 + r/n)^(nt) + PMT * [((1 + r_eff)^(N_contrib) - 1) / r_eff] Where: P = Principal (initial investment) r = Annual interest rate (decimal) n = Number of times interest is compounded per year t = Number of years PMT = Regular contribution amount r_eff = Effective rate per contribution period N_contrib = Total number of contribution periods
Imagine you have £5,000 saved and want to add £200 monthly to an account earning 4% annual interest, compounded monthly. You plan to save for 5 years. Using the calculator, you'd input: Principal: 5000 Annual Rate: 4 Contribution Amount: 200 Contribution Frequency: Monthly Compounding Frequency: Monthly Years: 5 The calculator would show your total future value, including the initial principal and all your monthly contributions, plus the interest earned.
Compound interest is interest calculated on the initial principal, which also includes all of the accumulated interest from previous periods. It's often called 'interest on interest' and can significantly boost your savings over time.
Regular contributions, like monthly deposits, add more principal to your savings. This extra principal then starts earning interest, which also compounds. This creates a powerful snowball effect, accelerating your wealth growth much faster than just relying on an initial lump sum.
Compounding frequency is how often your earned interest is added to your principal (e.g., monthly, quarterly, annually). Contribution frequency is how often you add new money to your account. They can be the same or different, and our calculator handles both scenarios.
Yes, this calculator can be a great tool for estimating potential retirement savings, especially if you make regular contributions to a pension or investment account. However, remember that actual returns can vary, and this tool provides an estimate based on a fixed interest rate.
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