Calculate My Interest on Savings Account

Calculate your savings account interest with our free online calculator. Whether you're saving for a short-term goal or long-term retirement, understanding how interest accumulates can help you make smarter financial decisions.

How Savings Interest Works

Savings accounts typically offer interest calculated on a regular basis, usually monthly or annually. The interest rate is applied to your account balance, and the amount earned is credited to your account. There are two main types of interest calculations:

Simple Interest

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

Simple Interest = Principal × Rate × Time

Where:

Principal = the initial amount of money
Rate = annual interest rate (in decimal)
Time = time the money is invested (in years)

With simple interest, the interest amount remains constant over time. This type of interest is common in short-term savings accounts.

Compound Interest

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 = Principal × (1 + Rate/Compounding Periods)^(Rate × Time) - Principal

Where:

Principal = the initial amount of money
Rate = annual interest rate (in decimal)
Compounding Periods = number of times interest is compounded per year
Time = time the money is invested (in years)

Compound interest can significantly grow your savings over time, especially with longer investment periods. Most savings accounts offer compound interest, typically calculated monthly.

Note: The effective annual rate (EAR) is what you'll actually earn in a year, considering the compounding frequency. For example, a 1% monthly compounding rate with 12 periods per year results in an EAR of 12.68%.

The Interest Formula

The exact formula used depends on whether your savings account offers simple or compound interest. Our calculator uses the compound interest formula by default, as it's the most common type in savings accounts.

Future Value = Principal × (1 + Rate/Compounding Periods)^(Compounding Periods × Time)

Where:

Future Value = the amount of money accumulated after n years, including interest
Principal = the initial amount of money
Rate = annual interest rate (in decimal)
Compounding Periods = number of times interest is compounded per year
Time = time the money is invested (in years)

From this formula, you can calculate the interest earned by subtracting the principal from the future value.

Worked Examples

Let's look at two examples to illustrate how savings interest calculations work.

Example 1: Simple Interest Calculation

Suppose you deposit $1,000 in a savings account with a simple annual interest rate of 2% for 3 years.

Simple Interest = $1,000 × 0.02 × 3 = $60

After 3 years, you'll have $1,060 in your account.

Example 2: Compound Interest Calculation

Now, let's assume the same $1,000 is invested in a savings account with a 2% annual interest rate compounded monthly for 3 years.

Future Value = $1,000 × (1 + 0.02/12)^(12 × 3) ≈ $1,061.68

After 3 years, you'll have approximately $1,061.68 in your account, earning $61.68 in interest.

Notice how compound interest results in a slightly higher amount than simple interest for the same principal and rate over the same period.

Frequently Asked Questions

How often is interest calculated in savings accounts?: Most savings accounts calculate interest monthly, though some may offer daily or annual compounding. The frequency affects how quickly your money grows.
What's the difference between APR and APY?: APR (Annual Percentage Rate) is the simple annual interest rate, while APY (Annual Percentage Yield) takes into account compounding, showing the actual annual return. For example, a 1% APR with monthly compounding might result in a 1.01% APY.
Is there a penalty for withdrawing money from a savings account?: Some savings accounts have withdrawal limits or penalties for frequent withdrawals. Always check your account terms to understand any restrictions.
How can I maximize my savings interest?: To maximize your interest, consider opening a high-yield savings account, keeping your money in the account for as long as possible, and taking advantage of any bonuses or promotions offered by the bank.
What happens if I don't pay minimum balance requirements?: If you don't maintain the minimum balance required by your savings account, you may lose the interest benefits or even be charged fees. Always check your account agreement for specific requirements.