CD Ladder Yield Calculator
A certificate of deposit ladder lets you earn the higher rates that longer terms usually pay while still keeping part of your money within easy reach. The idea is to split your savings across several CDs that mature in different years, so something is always coming free to reinvest at whatever rate prevails then. This calculator answers the most practical question about a ladder: what single yield am I actually earning across all of it? That number is the blended annual percentage yield, a dollar-weighted average of the APY on each rung. A rung holding more money counts for more in the average, so the blended figure leans toward where your dollars actually sit. Enter the amount and the APY for each of up to four rungs, and the tool returns the total deposited, the dollar-weighted blended APY, and the projected one-year interest at that rate. This lets you compare a laddered strategy against a single CD or a savings account on equal terms. Every figure is computed deterministically from the weighted-average rule, with a worked example below that reconciles exactly to the calculator so you can follow the arithmetic and trust the result down to the last cent.
The blended yield of a CD ladder is a dollar-weighted average of the rung rates: blended APY = sum(amount x APY) / total amount. With four equal 10,000 rungs at 4.00%, 4.25%, 4.50% and 4.75%, the blended APY is 4.38% on 40,000, about 1,750.00 of interest in the first year.
Blended APY formula
Blended APY = ( sum of (amount_k x APY_k) ) / ( sum of amount_k )
amount_k = dollars in rung k
APY_k = annual percentage yield of rung k
First-year interest = total amount x blended APY
Each rung's rate is weighted by the dollars in it. When the rungs hold equal amounts the weights cancel and the blended APY is simply the average of the rung rates.
Worked example
Four rungs of 10,000 each, earning 4.00%, 4.25%, 4.50% and 4.75%.
- Total deposited = 10,000 x 4 = 40,000.
- Weighted sum = 10,000 x (4.00 + 4.25 + 4.50 + 4.75) = 10,000 x 17.50 = 175,000.
- Blended APY = 175,000 / 40,000 = 4.375, which rounds to 4.38%.
- First-year interest = 40,000 x 4.375% = 1,750.00.
These are the calculator's default inputs, so the result above matches the widget exactly.
CD ladder yield calculator: frequently asked questions
What is a CD ladder?
A CD ladder is a set of certificates of deposit that mature at staggered dates, for example one each year for four years. As each rung matures you reinvest it into a new longer-term CD. This gives you regular access to part of your money while still earning the higher rates that longer terms usually pay.
What is blended APY?
Blended annual percentage yield is the weighted average of the APYs across all rungs, with each rung weighted by the dollars in it. If every rung holds the same amount, the blended APY is the simple average. If the amounts differ, larger rungs pull the blended figure toward their own APY.
Why ladder instead of one long CD?
A single long CD locks all your money away until one date and exposes you to rate risk if rates rise. A ladder spreads maturities so a portion is always coming free to reinvest at current rates, smoothing out rate changes while keeping most of your money in higher-yielding longer terms.
Are CDs safe?
Certificates of deposit at banks insured by the Federal Deposit Insurance Corporation are protected up to the standard insurance limit per depositor, per bank, per ownership category. Credit union CDs are similarly insured by the National Credit Union Administration. Always confirm the institution is insured before depositing.
What is the blended APY formula?
Blended APY equals the sum of (amount in each rung times its APY) divided by the total amount across all rungs. This is a dollar-weighted average. When all rungs hold equal amounts, it reduces to the plain average of the rung rates.
Official sources
- Certificates of deposit, APY and saving basics: US Securities and Exchange Commission, Investor.gov. As at 25 June 2026.
Reviewed by the CalculatorHub team, edited by James Graham, 25 June 2026. See our methodology. This is general information, not financial, tax, legal or investment advice.