The assumptions matter.
How we build educational comparisons—and where their limits begin.
What our comparisons are designed to do
Our comparisons explain product structures and measurement conventions. They do not rank current providers or identify the highest currently available rate. A reference to “top CD rates” describes a reader's comparison task, not a claim that we surveyed the entire market or verified every offer.
We separate deposit APY, bond yield measures, and dividend yield before comparing them. Products with different access rules, credit exposure, or price risk should not be treated as interchangeable merely because they display a percentage.
Five fields we keep visible
We ask readers to identify the product, the meaning of its yield measure, the time period, the access conditions, and the risks or costs that can change the outcome. For a real offer, those details come from current provider documentation. For an example, they are stated assumptions.
A useful comparison can include two scenarios: the intended holding period and an earlier exit or other changed condition. This is a way to expose an assumption, not a forecast that the changed condition will occur.
The arithmetic behind the homepage
The hypothetical deposit panels show a $10,000 balance at a constant 4.00% APY for exactly one year with interest retained, no other account activity, and no fees or taxes. Under those assumptions, interest is $400. A variable savings rate need not remain constant, and a CD requires checking its own day count and terms.
The bond panel shows $50 in annual coupon payments divided by a hypothetical $950 price, or about 5.26% current yield. It does not calculate yield to maturity or include a capital gain or loss. The dividend panel shows an assumed $2 annual payment divided by a $50 share price, or 4.00%. It does not promise that payment or include a change in share value.
What we leave out of a simple illustration
A compact educational calculation may omit taxes, transaction costs, changing balances, reinvestment choices, or security-specific features. An omission must be stated where it affects the interpretation. A full personal projection would require additional information not collected by this site.
We do not add a compounding adjustment to APY as though it were a nominal interest rate. We do not add dividends to a total-return measure that already includes them. Where a quoted measure already incorporates a fee, a second deduction could overstate its effect.
Sources, scope, and limitations
Use the source library to check the official explanations supporting these concepts. The planning worksheet provides a structure for researching an actual product. No provider search-volume metrics, live quotes, affiliate rankings, proprietary risk scores, or suitability ratings are used in the comparison.
The site does not verify your deposit insurance position, account eligibility, tax treatment, or investing circumstances. Read the actual disclosures and obtain qualified help for personal decisions. Our goal is a comparison that can be explained, not a promise that a particular choice will outperform.