Short answer: a CD’s APY already includes compounding, so your maturity value is deposit × (1 + APY) raised to the term in years. This calculator shows that value, the interest earned, and — the part most CD pages skip — whether the CD actually beats a high-yield savings account at the rates you enter. Example: $10,000 at 4.5% APY for 12 months matures at $10,450; the same money at a 4.0% HYSA reaches $10,400 — the lock-up earns you just $50.
| Interest earned | — |
| Same money in the HYSA instead | — |
| CD advantage (could be negative!) | — |
See the full breakdown
Educational estimate only — not financial advice. Because APY is already an effective annual rate, maturity value = deposit × (1 + APY)^(months/12) — compounding frequency is baked into APY by law. The HYSA comparison assumes that APY stays constant, which real savings rates do not; early-withdrawal penalties and taxes are not included.
How this calculator works
Banks must quote APY as an effective annual yield, so no compounding-frequency guesswork is needed: value = P(1 + APY)^t, with t in years (months ÷ 12 for partial terms). The comparison applies the identical formula at the savings-account APY. What the formula can’t capture: HYSA rates float (they can drop mid-term), and CD early-withdrawal penalties can claw back months of interest. Both caveats are printed next to the result, because they decide real-world winners.
Worked example
- $10,000 at 4.5% APY, 12 months → maturity $10,450, interest $450; HYSA at 4.0% → $10,400; CD advantage $50.
- Longer term: $25,000 at 5.0% APY, 24 months → $27,562 (interest $2,562).
- Short term: $5,000 at 3.0% APY, 6 months → $5,074.
FAQs
APY vs APR — which does a CD quote? CDs quote APY (what you actually earn in a year, compounding included). Loans quote APR. Comparing a CD’s APY to a loan’s APR directly is apples to oranges. What happens if I withdraw early? Typically a penalty of 3–12 months’ interest, and it can eat into principal on short terms. It’s the main reason the HYSA comparison matters. Is my CD insured? At an FDIC-insured bank (or NCUA-insured credit union), yes — up to $250,000 per depositor, per institution, per ownership category.
Sources: FDIC: understanding deposit insurance ($250,000), FDIC national rates and rate caps Figures last verified Report a wrong number