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日付の加算・減算
基準日から日・週・月・年を加算または減算して、日付・曜日・合計日数を正確に求めます。
お気に入りにするとホームですぐに探せます
How to use it
1Step 1Fill in Base date
2Step 2Change a value and the result updates instantly
3Step 3Save or copy the result
If the result looks off
The result looks wrong
Check the units and the baseline first. Changing a value updates the result instantly.
I want the starting values back
Press reset to return to the initial state.
よくある質問
How are months handled?
Calendar-based, so one month after January 31 is clamped to the end of February.
Does it tell me if the result is a weekend?
Yes. The result shows the weekday and flags weekend dates.