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CD Calculator

1-Year CD Calculator

See what twelve months in a CD actually earns.

満期時
$26,062.50
利息
$1,062.50
あなたの定期預金
$
%

金利の表示方法

1 年

一般的な期間

複利頻度

満期時の金額
$26,062.50
受取利息の合計
$1,062.50
実効年利回り APY
4.25%

1 年 の定期預金に $25,000.00、金利 4.25% APY、日次複利で $26,062.50 に増加 — 利息は $1,062.50、月平均 $88.54 です。

期間中の残高

元本利息
数値を表で表示
期間中の残高
か月目元本利息残高
開設時$25,000.00$0.00$25,000.00
2mo$25,000.00$174.03$25,174.03
5mo$25,000.00$437.34$25,437.34
7mo$25,000.00$614.41$25,614.41
10mo$25,000.00$882.33$25,882.33
1y$25,000.00$1,062.50$26,062.50

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.

  • 無料 — 登録不要
  • 入力と同時に更新
  • ブラウザ内で動作

計算式とコンテンツの最終確認日 . 銀行の金利は頻繁に変動します。最新の金利は必ずご利用の金融機関に直接ご確認ください。

結論から

How much does a 1-year CD earn?

A 1-year CD is the reference term for the whole market — it is the one where the quoted APY and the return you actually receive are the same number. A $25,000 deposit at 4.25% APY earns exactly $1,062.50 and matures at $26,062.50; $10,000 earns $425.00, which is $35.42 a month if you take the interest as income. Because the term matches the annualisation period, no conversion is needed and comparison against any other saving option is direct. The thing that most often goes wrong with a 12-month CD is not the rate but the renewal: the term rolls automatically at the end of a 7-to-10-day grace period, at whatever the bank's standard 12-month rate is on that day. Savers who opened on a promotional rate and did nothing at maturity frequently find the second year paying a full percentage point less than the first.

計算式と手法

計算方法

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

At a one-year term the exponent collapses to n, and the APY is exactly the return you receive.

A
Maturity value after twelve months
P
Opening deposit
r
Nominal annual rate as a decimal
n
Compounding periods per year (daily = 365)
t
1 — the term in years

手順

  1. 1

    If the bank quoted an APY, multiply the deposit by (1 + APY) and you are finished.

  2. 2

    If it quoted a nominal APR, divide by n and raise (1 + r/n) to the power n.

  3. 3

    Multiply by the deposit for the maturity value.

  4. 4

    Subtract the deposit for the year's interest.

  5. 5

    Divide that by twelve for the monthly interest figure, if you plan to draw it.

ガイド

この計算機の使い方

4つの入力だけで、結果はその場で表示されます。送信も会員登録も不要です。
  1. 1

    Enter your deposit

    Type the amount or drag the slider. Twelve-month CDs generally carry the lowest minimums on the sheet, often $500 or $1,000.

  2. 2

    Enter the 12-month rate

    Set the toggle to APY if that is how the bank quoted it. On a one-year term an APY needs no conversion — the maturity value is simply deposit × (1 + APY).

  3. 3

    Check the monthly figure

    Divide the year's interest by twelve if you intend to draw the interest rather than compound it. Drawing it lowers the maturity value.

  4. 4

    Plan the renewal now

    Note the maturity date and the grace period before you open. That single step is worth more than a 0.10% better rate.

計算例

実際の数値を最後まで計算しています。ご自身の数字と照らし合わせて、計算機の結果を確かめられます。

A $25,000 deposit in a standard 12-month CD

入力値

Deposit
$25,000
Rate
4.25% APY
Term
12 months

結果

Interest earned
$1,062.50
Maturity value
$26,062.50
Monthly interest
$88.54

At a one-year term the APY and the realised return are identical — 4.25% quoted, 4.25% received. This is the only term where that is true, which is why the 12-month CD is the standard benchmark for comparing offers.

A promotional CD left to auto-renew at the standard rate

入力値

Deposit
$25,000
Year 1 — promotional
4.25% APY
Year 2 — standard rate on renewal
3.25% APY

結果

Balance after year 1
$26,062.50
Balance after year 2
$26,909.53
Year 2 interest
$847.03
Cost of not acting
$260.63

Missing the grace period cost $260.63 in a single year — more than a quarter of the first year's interest, and far more than any realistic difference between two banks' opening rates. Diarise the maturity date the day you open the CD.

算出方法

精度と前提条件

どの計算機にも前提条件があります。当サイトの前提を明記しますので、この数値が何を織り込み、何を織り込んでいないかがはっきり分かります。
  • Interest is retained in the CD. Taking the monthly interest as income lowers the maturity value, because the withdrawn interest stops compounding.

  • The rate is fixed for the full twelve months, which is standard for a fixed-rate CD but not for a step-rate or bump-up product.

  • The renewal example uses an illustrative standard rate. Check your own bank's non-promotional 12-month rate — the gap is often wider than the one shown.

  • Figures are gross of tax. A full year of interest above $10 is reported to the IRS on Form 1099-INT.

計算の慣行は、米国の金融機関が預金口座のAPYを開示する方法を定めたRegulation DD(12 CFR 1030)に従っています。付保対象の金融機関への預金は、預金者ごと・銀行ごと・所有区分ごとに$250,000までFDICで保護されます。

一次情報

これらのルールの出どころ

この計算機が従う慣行は、当サイトではなく規制当局が定めたものです。各項目は定めている機関にリンクしていますので、当サイトの説明を信じるのではなく、ご自身で確認いただけます。

詳細

重要なポイントとルール

CDを開設または継続する前に知っておきたい要点をまとめました。
  • One year is the only term where APY and realised return coincide, which makes it the natural unit for comparing everything else. A 4.40% six-month CD and a 3.80% five-year CD are both quoted per year so they can be lined up against this one.

  • Auto-renewal is the default at nearly every institution. The grace period is typically 7 to 10 calendar days from maturity, and it is the only window in which you can move the money without a penalty.

  • Promotional 12-month rates almost never renew at the promotional rate. Treat the second year as unpriced until you see the sheet on the maturity date.

  • A 13-month or 15-month promotional CD is often priced above the standard 12-month term. If your horizon has any give in it, check the odd terms before defaulting to twelve.

  • Early withdrawal on a one-year CD is typically penalised at 90 days of interest. Breaking a $25,000 CD at 4.25% after six months costs $261.99 against $525.72 earned — you keep roughly half.

活用シーン

この計算機が役立つ方

  • Savers with a one-year horizon

    Money for a car, a wedding or a tax bill twelve months out. The date is known, the rate is fixed, and the comparison against any alternative is direct because everything is quoted annually.

  • Ladder builders

    The 12-month rung is the backbone of most CD ladders. Once a five-rung ladder is mature, one rung comes due each year and gets reinvested at the longest term.

  • Anyone renewing an existing CD

    If a CD is coming due, this page prices the renewal against what you could get by moving. The grace period is short — knowing the number before it opens is what makes acting possible.

よくある質問

1-Year CD Calculatorのよくある質問

この計算について最も多く寄せられる質問への、直接的な回答です。さらに詳しくは FAQハブをご覧ください。
  • At 4.25% APY, exactly $1,062.50 — maturing at $26,062.50, or $88.54 a month if you draw the interest. On a one-year term the APY is the return, so no conversion is needed.

セキュリティとプライバシー

入力した数値がブラウザの外に出ることはありません

当サイトの計算はすべて、ご自身の端末上でJavaScriptとして実行されます。アカウントもサーバーへの通信もなく、入力された数値にアクセス解析が紐づくこともありません。
  • 銀行と同じ標準的な計算式

    Regulation DDのもとで銀行が用いるのと同じ、複利とAPYの慣行を使用しています。

  • 完全無料・ログイン不要

    登録もメールアドレスの入力も課金もありません。すべての計算機を、初回から制限なくお使いいただけます。

  • データがブラウザの外に出ることはありません

    すべての計算はJavaScriptによりブラウザ内で実行されます。サーバーへの送信も保存も行いません。

HTTPSで配信しており、混在コンテンツはありません。詳しくは プライバシーポリシー をご覧ください。すべての数値の根拠となる 計算式と算出方法 も公開しています。

Price your twelve months

See the interest, the monthly figure and what auto-renewal at a lower rate would cost you.