CD Calculator
See what a certificate of deposit earns by maturity, after tax, and if you cash out early
Your CD
Optional; CD interest is taxed as income
Most CDs charge a penalty of a few months of interest
Value at maturity
$10,450.00
$450.00 interest on $10,000 over 1 year · 4.500% APY
Interest earned
$450.00
APY
4.500%
yearly growth including compounding
Interest rate (APR)
4.402%
with daily compounding
Interest after tax
$450.00
add a tax rate to estimate
Balance as the CD grows
Interest compounds until maturity
What you get back
$10,450.00 after tax at maturity
Balance by Month
| Month | Interest Earned | Balance |
|---|---|---|
| 1 | $36.75 | $10,036.75 |
| 2 | $73.63 | $10,073.63 |
| 3 | $110.65 | $10,110.65 |
| 4 | $147.80 | $10,147.80 |
| 5 | $185.10 | $10,185.10 |
| 6 | $222.52 | $10,222.52 |
| 7 | $260.09 | $10,260.09 |
| 8 | $297.79 | $10,297.79 |
| 9 | $335.64 | $10,335.64 |
| 10 | $373.62 | $10,373.62 |
| 11 | $411.74 | $10,411.74 |
| 12 | $450.00 | $10,450.00 |
How CDs Work
A certificate of deposit pays a fixed rate for a fixed term in exchange for leaving your money untouched. Banks quote the APY, which already includes compounding, so a 4.5% APY on $10,000 grows to $10,450 in a year. In the US, CDs at FDIC-insured banks and NCUA-insured credit unions are covered up to $250,000 per depositor, per bank, per ownership category.
The Formulas
Balance = deposit × (1 + APY)^(months ÷ 12)
APY = (1 + APR ÷ n)^n − 1
Penalty ≈ deposit × APR × penalty months ÷ 12
Penalties vary by bank; check your CD's terms before withdrawing early.
Getting More From CDs
- •Compare APYs, not interest rates, across banks
- •Build a CD ladder so part of your money matures every year
- •Longer terms usually pay more but lock your money up longer
- •Watch for automatic renewal at maturity; you often get a short grace period
- •Interest is taxable each year even if it stays in the CD