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CD Calculator

3-Month CD Calculator

See what 90 days in a CD actually earns.

Bei Fälligkeit
25.264,52 $
Zinsen
264,52 $
Ihr CD
$
%

Zinssatz angegeben als

Mon.

3 Monate

Übliche Laufzeiten

Zinseszins-Intervall

Wert bei Fälligkeit
25.264,52 $
Gesamtzinsen
264,52 $
Effektiver APY
4,30%

25.000,00 $ in einem CD über 3 Monate zu 4,30% APY, täglich verzinst, wächst auf 25.264,52 $ — das sind 264,52 $ Zinsen, im Schnitt 88,17 $ pro Monat.

Guthaben über die Laufzeit

KapitalZinsen
Die Zahlen als Tabelle anzeigen
Guthaben über die Laufzeit
MonatKapitalZinsenGuthaben
Bei Eröffnung25.000,00 $0,00 $25.000,00 $
1mo25.000,00 $87,86 $25.087,86 $
2mo25.000,00 $176,04 $25.176,04 $
3mo25.000,00 $264,52 $25.264,52 $

Calculated in your browser using A = P(1 + r/n)nt. Nothing is sent to a server. Figures are before tax; confirm exact terms with your bank.

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Formeln und Inhalte zuletzt geprüft . Bankzinsen ändern sich häufig – bestätigen Sie die aktuellen Konditionen direkt bei Ihrem Institut.

Die kurze Antwort

How much does a 3-month CD earn?

A 3-month CD holds your deposit for about 90 days and pays a fixed rate for that period, after which it matures or renews. On a $25,000 deposit at 4.30% APY the term earns $264.52 and matures at $25,264.52; on $10,000 it earns $105.81. Because the term is short, two things follow that do not apply to longer CDs. First, the interest is small enough that a high-yield savings account paying within about 0.30% of the CD rate will usually leave you better off, since it keeps the money liquid for nothing. Second, the early withdrawal penalty — commonly 90 days of interest, which on a 90-day CD is all of it — can consume the entire return and, at many banks, dip into principal. A 3-month CD is therefore worth opening when the rate clearly beats savings and you are certain of the date you need the money back.

Formel & Methode

So wird gerechnet

A = P(1 + r/n)^(nt), t = 0.25

The standard compound growth formula with a quarter-year term. Three months is 0.25 years, or 91 days on a daily-compounding basis.

A
Maturity value after roughly 90 days
P
Opening deposit
r
Nominal annual rate as a decimal
n
Compounding periods per year (daily = 365)
t
0.25 — the term expressed in years

Schritt für Schritt

  1. 1

    Convert the advertised rate to a decimal and divide by n.

  2. 2

    Raise (1 + r/n) to the power of n × 0.25 — roughly 91 daily credits.

  3. 3

    Multiply by the deposit for the 90-day maturity value.

  4. 4

    Subtract the deposit to isolate the interest the quarter earned.

  5. 5

    Compare that figure against three months of high-yield savings interest before committing.

Anleitung

So verwenden Sie diesen Rechner

Vier Eingaben, sofortige Ergebnisse. Nichts abzuschicken und nichts zu registrieren.
  1. 1

    Enter the deposit

    Type the amount you plan to place for the quarter. Short promotional CDs often carry a higher minimum than the bank's standard terms.

  2. 2

    Enter the 3-month rate

    Use the rate quoted specifically for the 3-month term, not the bank's headline rate — the headline usually belongs to a different, longer term.

  3. 3

    Read the interest, not the balance

    On 90 days the maturity value looks almost unchanged. The interest figure is the number that tells you whether the term was worth it.

  4. 4

    Compare against staying liquid

    Check the same deposit for three months in a high-yield savings account. If the gap is small, the CD is buying you very little for the loss of access.

Beispiele

Rechenbeispiele

Echte Zahlen, vollständig durchgerechnet – damit Sie den Rechner gegen Ihre eigenen Werte prüfen können.

A $25,000 emergency reserve parked for one quarter

Eingaben

Deposit
$25,000
Rate
4.30% APY
Term
3 months

Ergebnis

Interest earned
$264.52
Maturity value
$25,264.52

A quarter at 4.30% returns $264.52. A high-yield savings account at 4.00% over the same 90 days would pay $246.34 and keep the money available — so the CD is buying $18.18 of extra return in exchange for locking up $25,000. That is a thin trade.

The same CD broken at day 45, with a 90-day interest penalty

Eingaben

Deposit
$25,000
Rate
4.30% APY
Withdrawn
Day 45 of 90
Penalty
90 days of interest

Ergebnis

Interest earned by day 45
$130.10
Penalty charged
$265.07
Shortfall taken from principal
$134.97

On a 3-month CD a 90-day penalty is larger than the interest the CD can possibly have earned before maturity. Federal rules permit the bank to take the difference out of principal, so breaking a short CD early can return less than you deposited. This is the defining risk of the term.

Methodik

Genauigkeit & Annahmen

Jeder Rechner trifft Annahmen. Hier sind unsere, klar benannt, damit Sie genau wissen, was die Zahlen berücksichtigen – und was nicht.
  • Three months is treated as 0.25 years. Banks count actual days, so a 91- or 92-day quarter pays marginally more than shown.

  • The rate is fixed for the term and interest is retained rather than paid out.

  • The comparison against savings assumes the savings rate holds for the full quarter. Savings rates are variable and can be cut at any time — that is the one advantage the CD has here.

  • Penalty figures use a 90-day-interest convention. Some banks charge one month of interest on short terms, others all interest earned; the disclosure states which.

Die Konventionen folgen Regulation DD (12 CFR 1030), die regelt, wie US-Institute den APY auf Einlagenkonten ausweisen. Einlagen bei versicherten Instituten sind durch die FDIC bis $250,000 je Einleger, je Bank und je Kontoart geschützt.

Primärquellen

Woher diese Regeln stammen

Die Konventionen, denen dieser Rechner folgt, werden von Aufsichtsbehörden festgelegt, nicht von uns. Jede verweist auf die herausgebende Stelle, damit Sie sie nachprüfen können, statt uns glauben zu müssen.

Einzelheiten

Wichtige Details und Regeln

Schnell erfassbare Fakten, die Sie vor dem Abschluss oder der Verlängerung eines CD kennen sollten.
  • A 90-day interest penalty on a 90-day CD means there is no window in which early withdrawal leaves you ahead. Regulation DD lets institutions take the shortfall from principal, and most reserve the right to.

  • 3-month CDs almost never carry the bank's best rate. Promotional pricing clusters at 6, 7, 11 and 13 months, because those are the terms banks use to attract deposits.

  • The term auto-renews unless you act. A 3-month CD renewing four times a year gives you four short grace periods to miss — set a calendar reminder for the maturity date the day you open it.

  • Because the term is under a year, the quoted APY is an annualised figure you will not actually receive. Earning 4.30% APY for three months yields about 1.06% of the deposit, not 4.30%.

  • Treasury bills at 13 weeks are the direct competitor. They are exempt from state and local income tax, which in a high-tax state can beat a nominally higher CD rate.

Anwendungen

Für wen dieser Rechner gedacht ist

  • Savers with a known 90-day horizon

    Money earmarked for a tax bill, a tuition instalment or a closing date in three months. The date is fixed, so the lock-up costs nothing and the rate is guaranteed.

  • Rate watchers waiting to commit

    If you expect rates to move soon, a 3-month CD holds a floor while keeping you three months from a decision — the shortest lock a CD offers.

  • Anyone comparing against savings

    The honest use of this page is often to talk yourself out of the CD. Run both numbers; on a short term the gap is frequently too small to justify the loss of access.

Häufige Fragen

3-Month CD Calculator – häufige Fragen

Direkte Antworten auf die Fragen, die zu dieser Berechnung am häufigsten gestellt werden. Mehr dazu in der FAQ-Übersicht.
  • About a quarter of the annual rate. At 4.30% APY a $25,000 deposit earns $264.52 over three months and $10,000 earns $105.81. The APY is annualised, so a three-month term delivers roughly 1.06% of the deposit rather than 4.30%.

Sicherheit & Datenschutz

Ihre Zahlen verlassen Ihren Browser nie

Jede Berechnung auf dieser Website läuft als JavaScript auf Ihrem eigenen Gerät. Es gibt kein Konto, keinen Serveraufruf und keine Analyse, die an Ihre Eingaben geknüpft wäre.
  • Formeln nach Bankstandard

    Verwendet dieselben Zinseszins- und APY-Konventionen wie Banken unter Regulation DD.

  • 100 % kostenlos, ohne Login

    Keine Registrierung, keine E-Mail-Hürde, keine Bezahlschranke. Jeder Rechner ist beim ersten Besuch voll nutzbar.

  • Ihre Daten verlassen Ihren Browser nie

    Jede Berechnung läuft clientseitig in JavaScript. Nichts wird an einen Server gesendet oder gespeichert.

Ausgeliefert über HTTPS ohne gemischte Inhalte. Lesen Sie unsere Datenschutzerklärung oder sehen Sie sich die Formeln und die Methodik hinter jeder Zahl an.

Is 90 days worth locking up?

Run your own deposit and compare the quarter's interest against leaving the money liquid.