CD Interest Calculator
Certificates of deposit lock in a fixed rate for a fixed term. This calculator shows your total interest and what the CD is worth at maturity.
How this calculator works
Banks advertise APY, which already reflects monthly compounding. The calculator applies the APY compounded monthly over the term: each month the balance earns one-twelfth of the APY, including interest on previous interest. The result is your total interest earned and the maturity value. A penalty usually applies if you withdraw before maturity — typically 90 days of interest for short terms, more for longer ones.
Frequently asked questions
What is the difference between APR and APY?
APR is the simple annual rate; APY includes the effect of compounding and is always slightly higher. Banks quote CD rates as APY, so the number you see is what you actually earn.
Are CDs FDIC-insured?
Yes — CDs from FDIC-insured banks are protected up to $250,000 per depositor, per bank, per ownership category, making them one of the safest places to park cash.
What happens if I withdraw early?
You pay an early-withdrawal penalty — commonly 90 days of interest on terms up to one year, and up to 6 months on longer terms. The penalty can wipe out most or all of your interest, so match the term to when you need the money.
Disclaimer: Results are estimates for general information only and do not constitute financial, tax, or legal advice. Figures reflect 2026 rules and may change. Always confirm current limits and consult a qualified professional before making decisions. Official figures: IRS.gov · 2026 limits per IRS tax inflation adjustments.