*Calculated based on compounded APY over the specified term.
Understanding the Marcus CD Calculator
The Marcus CD Rate Calculator is designed to help investors estimate the future growth of their savings when investing in Certificates of Deposit (CDs) offered by Marcus by Goldman Sachs. Unlike standard savings accounts, CDs typically lock your money for a fixed term in exchange for a guaranteed interest rate, represented as the Annual Percentage Yield (APY).
Key Feature: Marcus High-Yield CDs are known for competitive rates and no fees to open or maintain the account. The interest on these CDs typically compounds daily and is credited monthly, maximizing your yield over time.
How to Calculate CD Earnings
To determine how much your money will grow, this calculator uses the APY formula adjusted for the specific time frame you intend to keep the CD. The calculation logic is as follows:
Deposit Amount: The principal lump sum you invest at the start.
Term Length: The duration (in months) you agree to keep the funds in the account. Common terms range from 6 months to 6 years.
APY (%): The Annual Percentage Yield, which reflects the total amount of interest paid on the account based on the interest rate and the frequency of compounding for a 365-day period.
The Mathematical Formula
Since APY takes compounding into account for a one-year period, the future value ($A$) for terms different from exactly one year can be estimated using the exponentiation of the time factor ($t$ in years):
Future Value = Deposit × (1 + APY/100)(Months / 12)
Why Choose a Marcus CD?
10-Day Rate Guarantee: If the rate on your selected CD term goes up within 10 days of your account opening, Marcus will automatically give you the higher rate, ensuring you don't miss out on immediate hikes.
No-Penalty Options: While standard High-Yield CDs charge a penalty for early withdrawal, Marcus also offers "No-Penalty CDs" (typically 7, 11, or 13 months) that allow you to withdraw your full balance beginning seven days after funding without any fee, providing liquidity alongside growth.
Example Calculation
Let's say you invest $20,000 in a 12-month High-Yield CD with a 5.00% APY.
Initial Deposit: $20,000
Calculation: $20,000 × (1 + 0.05)1
Total at Maturity: $21,000
Interest Earned: $1,000
If the term was only 6 months, the calculation would be $20,000 × (1.05)0.5 ≈ $20,493.90, yielding roughly $493.90 in interest.
function calculateCDReturns() {
// 1. Get input values by ID
var depositInput = document.getElementById('depositAmount');
var termInput = document.getElementById('cdTerm');
var apyInput = document.getElementById('apyRate');
var errorDiv = document.getElementById('errorMessage');
var resultsDiv = document.getElementById('resultsSection');
// 2. Parse values
var principal = parseFloat(depositInput.value);
var months = parseFloat(termInput.value);
var apy = parseFloat(apyInput.value);
// 3. Validation
if (isNaN(principal) || isNaN(months) || isNaN(apy) || principal < 0 || months <= 0 || apy < 0) {
errorDiv.style.display = 'block';
resultsDiv.style.display = 'none';
return;
}
errorDiv.style.display = 'none';
// 4. Calculation Logic
// Formula: Future Value = P * (1 + r)^t
// r = APY as decimal
// t = years (months / 12)
var rateDecimal = apy / 100;
var years = months / 12;
var totalValue = principal * Math.pow((1 + rateDecimal), years);
var interestEarned = totalValue – principal;
// 5. Formatting Output
// Helper function for currency formatting
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2,
maximumFractionDigits: 2
});
document.getElementById('displayPrincipal').innerText = formatter.format(principal);
document.getElementById('displayInterest').innerText = formatter.format(interestEarned);
document.getElementById('displayTotal').innerText = formatter.format(totalValue);
// 6. Show results
resultsDiv.style.display = 'block';
}