Savings and CD Calculators

Every calculator here runs entirely in your browser. Nothing you type is sent anywhere, stored, or logged, and none of them asks for an email address. They exist because most deposit questions come down to arithmetic that is tedious by hand and easy to get subtly wrong.

Start from the decision, not the tool

Picking a calculator by name is the slow way in. Find the question you are actually asking:

• How much will my savings actually earn? — Compound interest calculator: What a balance grows to at a given APY, year by year.
• Should I break this CD? — CD early withdrawal calculator: Whether breaking a CD to chase a higher rate leaves you ahead.
• How do I split money across CD terms? — CD ladder builder: Splits an amount into rungs and shows when each one frees up.
• Which of these two offers keeps more of my money? — Two-offer comparison calculator: Puts two accounts on one denominator after fees and tax.
• Am I really getting the rate they advertised? — Statement APY earned calculator: Works out the rate you actually received from one statement.
• Which tier am I in, and what does it pay? — Tiered rate calculator: Shows what a tier table pays under each of the two methods banks use.
• Is my money actually growing? — After-tax and inflation-adjusted return calculator: What is left of a yield once tax and inflation are taken out.
• Is this account's fee eating my interest? — Account fee break-even calculator: The balance below which a monthly fee turns the account into a loss.
• Lock the rate or stay liquid? — Fix it or float it calculator: A locked CD against a variable account across three rate paths.
• Is all of my money insured? — FDIC coverage calculator: Insured and uninsured amounts across banks, owners, and beneficiaries.

What every one of these assumes

A calculator is only as honest as the assumptions behind it, so here are the ones that run through all of them. Each tool repeats the assumptions specific to it directly under the inputs.

APY is not the same number as the interest rate. APY already contains the effect of compounding; the stated or nominal rate does not. Banks disclose both, and putting one where the other belongs is the single most common way these calculations go wrong. Where a tool needs the nominal rate — the early withdrawal calculator, because penalties are charged as simple interest at that rate — it converts your APY back rather than asking you to look up a second figure.

Your balance is treated as fixed unless the tool says otherwise. That is contractually true for a CD. For a savings or money market account it is a simplification: you will add and withdraw money, and the rate itself can change at any time without notice, because those rates are variable by design under Regulation DD.

Results are before tax unless tax is an input. Deposit interest is ordinary income in the year it is credited. A 4% yield is not 4% in your pocket, and the gap widens with your marginal rate. Only the after-tax calculator applies that adjustment.

Fee waivers are assumed to hold. If a monthly fee is waived by direct deposit or a minimum balance, entering zero assumes you meet that condition every single cycle. Miss one month and the fee applies in full for that month, which is exactly the case the fee break-even tool is built to price.

Rate paths are your assumption, not a forecast. Where a tool asks what happens if rates move, it is asking you to state a scenario. Nothing here predicts what the Federal Reserve will do, and neither does anyone else with reliable accuracy.

Where the numbers you need are written down

Most inputs come from one document. Under the Truth in Savings Act, banks and credit unions have to disclose the annual percentage yield, the compounding and crediting method, any minimum balance requirement, the fee schedule, and — for a CD — the early withdrawal penalty formula and whether it can reach your principal. That disclosure is given to you before the account opens and is available on request afterwards.

Two figures are worth pulling from your statement rather than the marketing page: the interest actually credited for the period, and the average daily balance it was calculated on. Those two numbers, with the number of days in the statement period, tell you the yield you received rather than the one you were quoted. If those disagree by more than a rounding difference, the reason is usually a tier you dropped below or a fee that was charged.

What these tools deliberately do not do

None of them look up current rates. There is no live feed here, no ranked list of banks, and no affiliate links to accounts. Deposit rates change without notice and vary by state, balance tier, and relationship status, so any number this site published would be wrong for some readers on the day they read it. Instead the tools take the figures from the offer in front of you and tell you what they mean.

They also do not give advice. A calculator can tell you that breaking a CD costs $169 and gains $144, which settles the arithmetic. Whether the flexibility is worth $25 to you is a judgment about your own circumstances that no formula reaches.

If you would rather read first

Each calculator sits inside an article that explains the decision in full — when the calculation matters, what the edge cases are, and what the regulations require. The tool pages link through to them, and the topics index lists everything by subject.