日付計算機

任意の日付に年、月、週、日、時間、分、秒を加算または減算します。締め切り計算、計画、日付計算に最適です。

上記の計算を設定して結果を確認してください

How to Add or Subtract Time

Quickly calculate future or past dates by adding or subtracting years, months, days, hours, and minutes.

1. Set Start Date

Choose your reference point. Use "Now" for real-time calculations.

2. Pick Duration

Use quick presets like "1 year" or type a custom string like "2w 3d".

3. Toggle Operation

Switch between adding or subtracting time to find future or past dates.

Complex Date Logic

Our algorithm correctly handles varying month lengths, leap years, and daylight saving time transitions.

Example: Adding 1 month to January 31st correctly results in February 28th (or 29th in a leap year).

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Frequently Asked Questions

当社の日付加算/減算計算機を使用する理由

Quick Presets

One-click durations from 15 minutes to 1 year.

カスタム期間

任意の時間単位の組み合わせを加算または減算します。

Add or Subtract

Calculate future dates or find past dates.

Export & Share

Export to calendar apps or share results instantly.