Calculate Interest Earned on Savings Account

Calculating the interest earned on your savings account is essential for understanding your financial growth. Whether you're using simple interest or compound interest, this guide will help you determine exactly how much you've earned over time.

How to Calculate Interest Earned

The interest earned on a savings account depends on the type of interest applied. Most savings accounts use either simple interest or compound interest. The key factors in the calculation are:

Principal amount (initial deposit)
Interest rate (annual percentage rate)
Time period (in years)
Compounding frequency (for compound interest)

Use our calculator to quickly determine your interest earnings based on these factors.

Simple Interest Calculation

Simple interest is calculated on the original principal amount only. The formula for simple interest is:

Simple Interest Formula

Interest = Principal × Rate × Time

Where:

Principal = Initial amount of money
Rate = Annual interest rate (in decimal)
Time = Time the money is invested (in years)

Simple interest is straightforward but doesn't account for the power of compounding over time.

Compound Interest Calculation

Compound interest is calculated on the initial principal and also on the accumulated interest of previous periods. The formula for compound interest is:

Compound Interest Formula

Amount = Principal × (1 + Rate/Compounding Frequency)^(Compounding Frequency × Time)

Interest Earned = Amount - Principal

Where:

Principal = Initial amount of money
Rate = Annual interest rate (in decimal)
Compounding Frequency = Number of times interest is compounded per year
Time = Time the money is invested (in years)

Compound interest can significantly increase your savings over time compared to simple interest.

Note

Most savings accounts compound interest monthly, quarterly, or annually. The more frequently interest is compounded, the more interest you earn over time.

Example Calculation

Let's look at an example to illustrate how interest calculations work.

Simple Interest Example

Suppose you deposit $1,000 at a simple interest rate of 5% for 3 years.

Using the simple interest formula:

Interest = $1,000 × 0.05 × 3 = $150

Total amount after 3 years = $1,000 + $150 = $1,150

Compound Interest Example

Using the same principal and rate, but with monthly compounding:

Amount = $1,000 × (1 + 0.05/12)^(12 × 3) ≈ $1,157.63

Interest Earned = $1,157.63 - $1,000 = $157.63

Notice that compound interest results in slightly more earnings than simple interest for the same period.

Frequently Asked Questions

How often is interest calculated on savings accounts?: Most savings accounts compound interest monthly, quarterly, or annually. The more frequent the compounding, the more interest you earn over time.
What's the difference between APR and APY?: APR (Annual Percentage Rate) is the simple annual interest rate, while APY (Annual Percentage Yield) includes the effect of compounding, showing the actual annual rate of return.
How does compounding affect my savings?: Compounding allows your interest to earn interest, which can significantly increase your savings over time. The more frequently interest is compounded, the greater the effect.
Is there a minimum balance required for savings accounts?: Yes, most savings accounts require a minimum balance to earn interest. Check with your bank for specific requirements.
Can I withdraw money from a savings account without penalty?: Some savings accounts allow unlimited withdrawals, while others may have restrictions or penalties for frequent withdrawals. Check your account terms.