Compare fairly
You cannot pick the better simple and compound interest deal until you are comparing the same months or years, the same balance or subtotal, and the same points and fees. Simple vs Compound Interest helps when two documents use similar words for different things.
What hides in the footnotes
Headline rates diverge in the fine print: how fees are financed, how interest days are counted, which balance accrues interest. It helps to read one explanation alongside another so you notice what you assumed.
One sentence per offer
Write one plain sentence for each offer: what rate, on what balance, over how long, with how much cash today. If you cannot write both, you are not ready to compare the headline percentages alone.
Checklist
| Line this up first | Why the “winner” changes |
|---|---|
| Same time unit? | A monthly rate and an annual rate are not the same thing. |
| Same balance? | A lower % on a larger balance can cost more than a higher % on a smaller one. |
| Same cash today? | Points and fees change APR and total cost—use dollars, not slogans. |
Same period, same balance, same cash up front Then compare total cost
Same years, both offers
Core lesson
Go deeper: Simple vs Compound Interest. Use the calculators below with your own loan or bill numbers, not only the examples on this page.
Use the calculator
FAQ
- Where is the main lesson?
Simple vs Compound Interest pulls the topic together in one place, with links to related lessons.
- Which calculator should I open first?
Use the first tool in the list for most questions. If you are reconciling payment rows on a schedule, pick amortization when it appears in the list.