CD Term Calculator

Understanding Certificates of Deposit

A certificate of deposit is one of the safest and most predictable savings vehicles available to individual investors. When you purchase a CD, you deposit a fixed amount of money with a bank or credit union for a predetermined period (the term), and in return, the institution pays you a guaranteed interest rate. At maturity, you receive your original deposit plus all accumulated interest.

I built this CD term calculator because choosing the right CD duration is one of the most impactful decisions in a fixed-income savings strategy. A few tenths of a percentage point in rate difference, combined with the right compounding frequency and term length, can translate to hundreds or even thousands of dollars in additional earnings on larger deposits.

CDs are insured by the FDIC (Federal Deposit Insurance Corporation) up to $250,000 per depositor, per institution, per ownership category. Credit union CDs (sometimes called share certificates) are insured by the NCUA (National Credit Union Administration) at the same $250,000 level. This insurance means your principal and accrued interest are protected even if the bank fails.

How CD Interest Is Calculated

CD interest uses the compound interest formula. The total value at maturity is calculated as:

A = P x (1 + r/n)^(n x t)

In this formula, A is the final amount, P is the principal deposit, r is the annual interest rate expressed as a decimal, n is the number of compounding periods per year, and t is the time in years. The interest earned is simply A minus P.

For a concrete example, consider a $10,000 deposit at 4.50% APR compounded monthly for 12 months. P = 10000, r = 0.045, n = 12, t = 1. The calculation is A = 10000 x (1 + 0.045/12)^(12 x 1) = 10000 x (1.00375)^12 = 10000 x 1.04594 = $10,459.40. Interest earned is $459.40.

The APY (Annual Percentage Yield) for this CD is 4.594%, which is higher than the 4.50% APR because of the monthly compounding effect. APY is calculated as (1 + r/n)^n - 1, or in this case (1 + 0.045/12)^12 - 1 = 0.04594 = 4.594%.

How Compounding Frequency Affects Earnings

The more frequently interest compounds, the more you earn. Here is how a $25,000 deposit at 4.75% APR performs over 2 years with different compounding frequencies:

The difference between annual and daily compounding on this example is $28.97. While that may seem small on a $25,000 deposit over 2 years, the gap widens significantly with larger amounts and longer terms. On a $100,000 deposit over 5 years at 5.00%, daily compounding earns $497 more than annual compounding.

CD Term Lengths and What They Mean for Your Money

Choosing the right CD term requires balancing three factors: the interest rate offered, your need for liquidity, and your outlook on future rate movements. Each common term length has its own characteristics and ideal use cases.

Short-Term CDs · 3 to 6 Months

Short-term CDs offer the most flexibility with the smallest commitment. They typically carry lower rates than longer terms, though this relationship inverted in 2023-2024 when the Federal Reserve held rates at improved levels and short-term CDs sometimes paid more than 5-year CDs.

A 3-month CD works well for parking cash you know you will need in the near future but want to earn more than a savings account. On $20,000 at 4.25%, a 3-month CD earns approximately $213 in interest. The early withdrawal penalty on a 3-month CD is usually 30 to 90 days of interest.

Six-month CDs represent a sweet spot for short-term savings. They offer modestly better rates than 3-month terms while still providing relatively quick access to your money. In 2026, competitive 6-month CD rates range from 4.10% to 4.60% at online banks.

Medium-Term CDs · 1 to 3 Years

The 1-year CD is the most popular term length in the United States. It provides a solid rate while limiting your commitment to a single year. As of early 2026, top 1-year CD rates range from 4.25% to 4.75% APY. On a $50,000 deposit at 4.50%, a 1-year CD earns approximately $2,297 in interest with monthly compounding.

Two-year and 3-year CDs are ideal when you believe current rates are attractive and want to lock them in before potential rate cuts. If the Federal Reserve begins lowering its benchmark rate, 2-year and 3-year CDs purchased today will continue earning at their locked-in rate while new CD rates decline. A $50,000 deposit in a 3-year CD at 4.35% APY earns approximately $6,822 in total interest.

Long-Term CDs · 4 to 10 Years

Long-term CDs lock in a rate for an extended period, which is advantageous when you expect rates to decline but introduces significant opportunity cost if rates rise instead. The early withdrawal penalties are also steeper, typically 365 days of interest or more on 5-year CDs.

A 5-year CD at 4.25% APY on $100,000 earns approximately $23,137 in total interest. A 10-year CD at 4.00% on the same deposit earns approximately $48,024. However, you must be confident you will not need the funds during that period, as early withdrawal could erase a significant portion of your earnings.

Current CD Rate Environment in 2026

The CD rate field in 2026 reflects a transitional period in monetary policy. After the Federal Reserve raised rates aggressively in 2022-2023 and held them through most of 2024, the central bank began cautiously cutting rates in late 2024 and into 2025. This has created an environment where CD rates are moderating from their 2023-2024 peaks but remain historically attractive.

The gap between national averages and top online bank rates is dramatic. Depositing $50,000 in a 1-year CD at the national average of 1.82% earns approximately $918, while the same deposit at a top online bank rate of 4.50% earns approximately $2,297. That is a $1,379 difference for the same term and the same FDIC insurance coverage. Shopping around for the best rate is one of the simplest ways to increase your CD earnings.

CD Laddering Strategy

A CD ladder is a structured approach to CD investing that balances earning potential with liquidity needs. Instead of putting all your money into a single CD, you divide it across multiple CDs with staggered maturity dates.

The classic 5-rung CD ladder works as follows. Take a total deposit of $50,000 and split it into five equal portions of $10,000. Invest each portion into CDs with terms of 1 year, 2 years, 3 years, 4 years, and 5 years. When the 1-year CD matures, reinvest it into a new 5-year CD. Continue this pattern each year. After 5 years, you have five 5-year CDs with one maturing every 12 months.

The benefits of this approach include regular access to funds (a CD matures every year), exposure to higher long-term rates (since most of your money is in 5-year terms after the initial build period), and protection against rate volatility (since you reinvest at whatever the current rate is each year).

Mini-Ladder for Shorter Horizons

If you want more frequent liquidity, a mini-ladder uses 3-month, 6-month, 9-month, and 12-month CDs. This gives you access to a quarter of your funds every 3 months while earning more than a traditional savings account. On $40,000 split into four $10,000 CDs at rates averaging 4.30%, you earn approximately $1,090 over the first year, compared to roughly $740 in a high-yield savings account at 3.70%.

Barbell Strategy

The barbell approach concentrates your deposits at two extremes: very short-term CDs for liquidity and very long-term CDs for yield. For example, put 40% in 3-month CDs and 60% in 5-year CDs. This provides regular access to a significant portion of your funds while the majority earns higher long-term rates. The barbell works well when you expect rates to remain stable or decline, as your long-term CDs lock in current rates.

Early Withdrawal Penalties

Understanding early withdrawal penalties (EWPs) is critical because they determine the true cost of accessing your money before maturity. Penalties vary widely between institutions and are not regulated by federal law (banks can set their own penalties).

Some penalties can eat into your principal if you withdraw very early in the term. On a 12-month CD with a 180-day interest penalty, withdrawing after just 60 days means the penalty exceeds the interest earned, and you get back less than you deposited. No-penalty CDs exist as an alternative, but they typically offer rates 0.25% to 0.75% lower than standard CDs.

Tax Considerations for CD Investors

CD interest is taxed as ordinary income at both the federal and state level (in states with income tax). This is an important factor that reduces your real return. For a depositor in the 22% federal tax bracket with a 5% state tax rate, the effective tax rate on CD interest is 27%.

On a $50,000 CD earning $2,297 in interest at 4.50% APY, the tax obligation would be $2,297 x 0.27 = $620, leaving after-tax earnings of $1,677. Your after-tax APY is effectively 3.35%, not 4.50%. This is why the tax rate input in this calculator is important for understanding your true return.

For multi-year CDs, banks generally report interest on a 1099-INT in the year it is credited to your account. With a CD that compounds and credits annually, you owe taxes each year on the credited interest even though the CD has not matured. Some investors prefer CDs in Roth IRA accounts, where interest grows and is withdrawn tax-free in retirement, or Traditional IRA accounts, where taxes are deferred until withdrawal.

Inflation and Real Returns

After accounting for both taxes and inflation, the real return on a CD can be surprisingly low or even negative. If your CD earns 4.50% APY, your marginal tax rate is 22%, and inflation runs at 3.0%, your real after-tax return is approximately 0.51%. The formula is: real return = [(1 + after-tax return) / (1 + inflation)] - 1.

This does not mean CDs are a poor investment. They serve a specific purpose: preserving capital with guaranteed returns and zero market risk. Comparing CD returns to stock market returns is comparing different asset classes with fundamentally different risk profiles.

CDs vs. Other Savings Vehicles

Understanding where CDs fit in the broader savings field helps you make informed allocation decisions.

CDs are the best choice when you want a guaranteed, fixed return and can commit your funds for a specific period. High-yield savings accounts are better when you need full liquidity. Treasury bills deserve consideration for investors in high-tax states because the interest is exempt from state income tax, which can make their effective after-tax yield higher than a CD with a nominally higher rate.

Jumbo CDs and Negotiated Rates

Jumbo CDs require minimum deposits of $100,000 or more and historically offered premium rates. The rate advantage of jumbo CDs has narrowed in recent years, with many online banks offering their best rates on standard CDs with no minimum or low minimums ($500 to $1,000). However, traditional banks and credit unions still sometimes offer 0.10% to 0.25% rate premiums on jumbo deposits.

For deposits above $250,000, spread your money across multiple FDIC-insured institutions to maintain full insurance coverage. Some depositors use brokered CDs (purchased through brokerage accounts) to access CDs from many banks through a single account, each individually insured up to $250,000.

Brokered CDs vs. Direct CDs

Brokered CDs are purchased through brokerage firms like Fidelity, Schwab, or Vanguard. They offer access to CDs from hundreds of banks with no early withdrawal penalty in the traditional sense. Instead, you can sell a brokered CD on the secondary market before maturity, but the sale price depends on current interest rates. If rates have risen since you bought the CD, you may sell at a loss. If rates have fallen, you may sell at a premium.

Direct CDs are purchased directly from a bank or credit union. They have straightforward early withdrawal penalties but no market value risk. For most individual investors, direct CDs offer simplicity and predictability that brokered CDs cannot match.

When to Open a CD

Timing your CD purchase involves understanding the interest rate cycle. In a falling rate environment, locking in current rates with medium-to-long-term CDs protects your earnings as new issue rates decline. In a rising rate environment, sticking with shorter terms lets you reinvest at higher rates sooner.

In 2026, with the Federal Reserve expected to continue gradual rate normalization, a moderate approach makes sense. Locking in 1-year to 3-year CDs at current rates preserves a good yield, while keeping some portion in short-term CDs or savings accounts provides flexibility to adjust if the rate path changes.

I suggest using this calculator to model several scenarios before opening a CD. Compare the earnings from a single long-term CD against a laddered approach, factor in your tax situation, and consider whether the early withdrawal penalty risk aligns with your liquidity needs.

modern CD Strategies for Maximizing Returns

Beyond the basic ladder, experienced CD investors use several additional strategies to improve their returns while managing risk and liquidity.

The Bullet Strategy

A bullet strategy concentrates all CD purchases toward a single maturity date. If you know you will need the funds for a house down payment in 3 years, you might stagger your purchases (buying 3-year CDs now, 2-year CDs in one year, and 1-year CDs in two years) so that they all mature at the same time. This approach locks in rates across different points in the interest rate cycle while ensuring all funds are available when you need them.

The advantage of a bullet strategy is that you capture rate diversity without sacrificing the timing of your funds. If rates drop between now and your target date, your earlier purchases at higher rates compensate. If rates rise, your later purchases benefit from the increase.

The CD Barbell in Practice

I mentioned the barbell strategy earlier, but a practical example illustrates its effectiveness. Suppose you have $100,000 to invest in CDs. A pure barbell puts $40,000 in 3-month CDs at 4.10% and $60,000 in 5-year CDs at 4.25%. After 3 months, the short-term CDs mature and you can either reinvest in new 3-month CDs at the current rate or move the funds if you need liquidity.

Over the first year, the short-term portion earns approximately $1,640 (4 quarters of interest on $40,000 at roughly 4.10%). The long-term portion earns approximately $2,550 in the first year. Total first-year earnings are roughly $4,190, which is comparable to putting the full amount in 1-year CDs at 4.35% (which would earn $4,413). The barbell earns slightly less but provides access to $40,000 every 3 months.

Rate-Optimized Laddering

Instead of splitting your deposit evenly across all rungs of a ladder, rate-optimized laddering allocates more money to the highest-yielding terms. If 2-year CDs are paying 4.50% while 1-year CDs pay 4.25% and 3-year CDs pay 4.15%, you would allocate a larger share to 2-year CDs to capture the inverted yield curve. This requires more active management but can produce 0.10% to 0.25% higher blended returns than a standard equal-weight ladder.

FDIC Insurance and CD Safety

CDs at FDIC-insured banks are among the safest investments available. The FDIC insurance covers up to $250,000 per depositor, per insured bank, per ownership category. This means a married couple can have up to $1,000,000 in FDIC coverage at a single bank across individual accounts, joint accounts, and retirement accounts.

For deposits exceeding these limits, the CDARS (Certificate of Deposit Account Registry Service) program distributes your deposit across multiple banks through a single institution, maintaining full FDIC coverage on each portion. Similarly, IntraFi Network Deposits (formerly ICS and CDARS) allow you to access multi-million-dollar FDIC coverage through one banking relationship.

In the history of the FDIC since its founding in 1933, no depositor has ever lost a penny of insured deposits. This 90+ year track record of absolute safety makes CDs a cornerstone of conservative investment strategies, particularly for money you cannot afford to lose.

What Happens When a Bank Fails

If your bank fails, the FDIC typically arranges for another bank to assume the failed bank's deposits. Your CD continues at the same rate and term with the acquiring bank. In the rare case where no acquiring bank takes over, the FDIC pays depositors directly, usually within a few business days. Insured depositors receive their full principal plus accrued interest up to the insurance limit.

During the bank stress events of 2023, all FDIC-insured deposits were fully protected, reinforcing the reliability of the insurance system. However, deposits above $250,000 at banks like Silicon Valley Bank required special government intervention to be made whole, highlighting the importance of staying within insurance limits.

CDs in Retirement Planning

CDs play a specific role in retirement portfolios, particularly for retirees who need predictable income and cannot afford principal loss. Financial planners often recommend a "bucket" approach where near-term expenses (1 to 3 years) are funded by CDs and money market accounts, mid-term needs (3 to 7 years) by bonds and bond funds, and long-term growth (7+ years) by stocks and equity funds.

A retiree with $500,000 in investable assets might allocate $100,000 to a CD ladder providing dependable income for the next 5 years. With annual expenses of $20,000 supplementing Social Security, a 5-year ladder with $20,000 per rung at an average rate of 4.25% generates approximately $2,125 in annual interest income while providing $20,000 in maturing principal each year to cover expenses.

CDs Inside IRA Accounts

Holding CDs inside a Traditional IRA or Roth IRA provides tax advantages. In a Traditional IRA, CD interest grows tax-deferred until withdrawal in retirement, when it is taxed as ordinary income. In a Roth IRA, CD interest grows completely tax-free, and qualified withdrawals in retirement are also tax-free.

For a depositor in the 22% federal tax bracket earning $4,500 in annual CD interest, holding those CDs in a Roth IRA saves $990 per year in federal taxes. Over a 20-year retirement, that tax savings alone amounts to nearly $20,000, not counting the additional growth from reinvesting the tax savings.

IRA CDs have the same FDIC coverage as regular CDs, with the $250,000 limit applying specifically to retirement accounts as a separate ownership category. This means you can have $250,000 in regular CDs and an additional $250,000 in IRA CDs at the same bank, all fully insured.

Special CD Types and Features

Beyond the standard fixed-rate CD, several specialized CD products offer unique features that may suit specific savings goals.

No-Penalty CDs

No-penalty CDs allow you to withdraw your full balance before maturity without paying an early withdrawal penalty. The tradeoff is a lower rate, typically 0.25% to 0.75% below a standard CD of the same term. If you are uncertain about whether you will need the funds before maturity, a no-penalty CD provides a rate slightly above savings accounts with full flexibility. Marcus by Goldman Sachs, Ally Bank, and CIT Bank are among the institutions offering competitive no-penalty CDs.

Bump-Up CDs

Bump-up CDs (also called step-up or raise-your-rate CDs) allow you to request a rate increase once or twice during the term if the bank's CD rates go up. This feature provides some protection against rising rates. However, the initial rate on a bump-up CD is typically lower than a standard CD, and the bump option usually allows you to match the bank's current offered rate for your remaining term, not exceed it.

Bump-up CDs work best in environments where you expect rates to rise but still want the security of a CD. If rates stay flat or decline, you are stuck with the lower initial rate.

Add-On CDs

Add-on CDs allow you to make additional deposits into the CD after the initial opening. Standard CDs do not permit additional deposits, so the add-on feature is useful if you want to build your CD balance over time at a locked rate. The rate on add-on CDs is generally competitive with standard CDs, though not all banks offer this product.

Callable CDs

Callable CDs give the issuing bank the right to redeem (call) the CD before maturity, typically after a specified call protection period. Banks call CDs when rates drop significantly, allowing them to stop paying the higher locked-in rate. Callable CDs offer slightly higher rates than non-callable CDs to compensate for this risk. If your callable CD is redeemed early, you receive your full principal plus earned interest, but you lose the future interest income you were counting on.

I generally advise individual investors to avoid callable CDs unless the rate premium is substantial (at least 0.50% above non-callable alternatives). The call risk creates uncertainty that undermines the primary benefit of CDs: predictability.

Historical Perspective on CD Rates

CD rates have varied dramatically over the decades, reflecting broader economic conditions and Federal Reserve policy. Understanding this history provides context for evaluating whether current rates are attractive.

The current CD rate environment of 4.0% to 4.75% for 1-year terms is historically favorable compared to the near-zero rates that prevailed from 2009 to 2021. While rates are unlikely to return to the double-digit levels of the early 1980s (which were driven by extreme inflation), the current rates offer meaningful income on savings for the first time in over a decade.

Building a Complete Savings Strategy with CDs

CDs work best as one component of a diversified savings strategy rather than the sole vehicle for your entire savings. I recommend a three-tier approach that balances liquidity, yield, and growth.

The first tier is your emergency fund, held in a high-yield savings account or money market account for instant access. This should cover 3 to 6 months of expenses. These funds should never be locked in CDs because the penalty for early withdrawal defeats the purpose of an emergency fund.

The second tier is your short-to-medium-term savings goals, which is where CDs perform best. Money for a down payment in 2 years, a planned purchase in 18 months, or a vacation fund for next year all benefit from the higher rates and guaranteed returns of CDs. A laddered approach provides regular liquidity while capturing competitive rates.

The third tier is long-term wealth building, which belongs in investment accounts holding stocks, bonds, and other growth-oriented assets. CDs generally underperform inflation on a long-term basis after taxes, so they are not suitable for 10+ year wealth accumulation goals. For retirement savings, a mix of equities and bonds within tax-advantaged accounts (401k, IRA) will almost certainly outperform CDs over 20 to 30 years.

By assigning each dollar of savings to the appropriate tier, you ensure that your money earns the best possible return for its intended time horizon while maintaining the liquidity and safety you need for each financial goal.

How to Choose the Right Bank for Your CD

The institution where you open your CD matters almost as much as the term and rate you select. Different types of financial institutions offer different advantages for CD investors.

Online banks consistently offer the highest CD rates because they have lower overhead costs (no physical branches, fewer employees per dollar of deposits). Banks like Marcus by Goldman Sachs, Ally Bank, Synchrony Bank, and Discover Bank routinely offer rates 2 to 3 percentage points above the national average for brick-and-mortar banks. The tradeoff is that you manage everything online or by phone, with no in-person banking relationship.

Credit unions are another strong option for CDs, which they call "share certificates." Because credit unions are member-owned nonprofits, they often pass savings to depositors through competitive rates. Some credit unions restrict membership to specific communities, employers, or organizations, but many have broadly available membership through partnering organizations.

Traditional banks (national and community banks) generally offer lower CD rates but provide in-person service and relationship benefits. If you already have a checking account, savings account, mortgage, or other products with a bank, they may offer a rate bonus of 0.10% to 0.25% for existing customers. Some banks also offer promotional CD rates periodically to attract new deposits.

When comparing banks, look beyond the rate to examine early withdrawal penalties, minimum deposit requirements, automatic renewal policies, and whether partial withdrawals are permitted. A bank offering 4.55% with a 365-day interest penalty for early withdrawal may be less attractive than one offering 4.45% with a 90-day penalty if there is any chance you might need the funds before maturity.

CD Renewal and Maturity Decisions

When your CD matures, you typically have a grace period (usually 7 to 14 days) to decide what to do with the funds. Your options include withdrawing the money, renewing at the bank's current rate, or moving the funds to a different bank for a better rate. If you take no action during the grace period, most banks automatically renew the CD at their current rate for the same term, which may be significantly different from your original rate.

I recommend setting a calendar reminder for 2 to 3 weeks before each CD maturity date. This gives you time to shop current rates across multiple institutions, calculate whether renewing makes sense given the current rate environment, and initiate a transfer if a competing bank offers a better deal. A 0.30% rate difference on a $50,000 CD over 2 years equals $300 in additional interest, making the comparison effort worthwhile.

If you are using a CD ladder, maturity dates are naturally staggered. Use each maturity as an opportunity to reassess your overall savings strategy, not just mechanically reinvest into the same term. If rates have dropped significantly since your last investment, you might extend the term to lock in a higher rate for longer. If rates have risen, a shorter term positions you to reinvest at an even better rate when it matures.

Common CD Investing Mistakes

Even experienced savers make mistakes with their CD investments. Avoiding these common pitfalls can save you hundreds or thousands of dollars over time.

• Accepting the first rate offered. Banks count on customer inertia. The rate your current bank offers on CDs is almost certainly lower than the best available rate. Spend 15 minutes comparing rates at online banks and credit unions before committing.
• Ignoring the auto-renewal trap. Banks automatically renew CDs at maturity if you miss the grace period. The renewal rate might be 1% to 2% lower than competitive alternatives, and you are locked in for another full term.
• Putting emergency fund money in CDs. CDs with withdrawal penalties are the wrong vehicle for emergency savings. Keep your emergency fund in a liquid high-yield savings account and only use CDs for money you are confident you will not need before maturity.
• Chasing the highest rate without checking the institution. Verify that the bank is FDIC-insured (or NCUA-insured for credit unions), check their customer reviews, and understand the penalty structure before depositing.
• Investing too heavily in one term length. Concentrating all your CD investment in a single term exposes you to reinvestment risk. If your 5-year CD matures and rates have fallen, you must reinvest at a lower rate. A ladder mitigates this risk.

CD Calculator Formulas and Worked Examples

Having the exact formulas and step-by-step examples helps you verify calculations and understand the math behind your CD earnings.

Simple Interest vs. Compound Interest

Simple interest is calculated only on the original principal. The formula is I = P x r x t, where I is interest earned, P is principal, r is the annual rate, and t is time in years. A $10,000 CD at 4.50% simple interest for 2 years earns $10,000 x 0.045 x 2 = $900. Simple interest is rarely used for CDs in practice, but understanding it helps clarify how compounding adds value.

Compound interest calculates interest on the principal plus previously earned interest. The formula is A = P x (1 + r/n)^(n x t). That same $10,000 at 4.50% compounded monthly for 2 years: A = 10000 x (1 + 0.045/12)^(12 x 2) = 10000 x (1.00375)^24 = 10000 x 1.09380 = $10,938.00. The interest earned is $938.00, which is $38 more than simple interest. The extra $38 represents interest earned on interest.

Calculating APY from APR

APY = (1 + APR/n)^n - 1, where n is the number of compounding periods per year. For a CD at 4.50% APR compounded daily: APY = (1 + 0.045/365)^365 - 1 = (1.0001233)^365 - 1 = 1.04603 - 1 = 0.04603 = 4.603%. For the same rate compounded monthly: APY = (1 + 0.045/12)^12 - 1 = (1.00375)^12 - 1 = 1.04594 - 1 = 0.04594 = 4.594%. The difference between daily and monthly compounding at 4.50% is 0.009 percentage points of APY, or roughly $0.90 per $10,000 per year.

Worked Example · 5-Year CD Ladder

Suppose you have $50,000 to invest in a 5-year CD ladder. You divide it into five $10,000 portions. Current rates at your bank are 4.30% for 1-year, 4.25% for 2-year, 4.15% for 3-year, 4.10% for 4-year, and 4.05% for 5-year CDs, all compounded monthly.

Year 1 CD: $10,000 at 4.30% for 1 year = $10,000 x (1 + 0.043/12)^12 = $10,439.13. Interest earned = $439.13.

Year 2 CD: $10,000 at 4.25% for 2 years = $10,000 x (1 + 0.0425/12)^24 = $10,877.15. Interest earned = $877.15.

Year 3 CD: $10,000 at 4.15% for 3 years = $10,000 x (1 + 0.0415/12)^36 = $11,325.01. Interest earned = $1,325.01.

Year 4 CD: $10,000 at 4.10% for 4 years = $10,000 x (1 + 0.041/12)^48 = $11,778.02. Interest earned = $1,778.02.

Year 5 CD: $10,000 at 4.05% for 5 years = $10,000 x (1 + 0.0405/12)^60 = $12,236.86. Interest earned = $2,236.86.

Total interest earned across the entire ladder: $439.13 + $877.15 + $1,325.01 + $1,778.02 + $2,236.86 = $6,656.17. The blended average return is approximately 2.66% per year on the $50,000 total across the staggered timeframes, but this is somewhat misleading since the money is committed for different durations. The actual rate of return per dollar-year invested is closer to 4.17%.