以下のガイドはまだ日本語に翻訳されていないため、英語で表示しています。計算機自体はすべて日本語に対応しています。
この計算機の使い方
- Choose a start date and an end date.
- Tick 'include end date' to count both the first and last day (for example, for a hotel stay counted in days rather than nights).
- Results update instantly.
計算式
Days are counted between calendar dates, so time zones and daylight saving time don't affect the result. The years-months-days breakdown counts whole calendar months, borrowing days from the previous month when needed.
Days = end − start (+1 if the end date is included)
Weeks = ⌊days ÷ 7⌋ remainder days
Example
- From 1 January 2026 to 1 March 2026: 31 + 28 = 59 days.
- That's 8 weeks and 3 days, or 2 months exactly.
よくある質問
Is the end date included?
By default no: the difference between today and tomorrow is 1 day. Tick the option to include it, which adds one day.
How are leap years handled?
Automatically. February 29 is counted when it falls between the dates.
What counts as a business day here?
Monday to Friday. For public holidays, use the business days calculator, where you can list dates to exclude.