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Add / Subtract Days

Adds a signed whole number of calendar days, rolling across month and year boundaries.

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How add / subtract days works

Adds a signed whole number of calendar days, rolling across month and year boundaries.

Try an example

2024-02-28 + 1 day → 2024-02-29.

Good to know

Date-only calculations use the Gregorian calendar and UTC day boundaries, so daylight-saving changes do not alter day counts. Years 0001–9999.

Your privacy

Processing happens on this device. We do not upload your input, put it in share links or save it to your favourites. Closing this tab discards the working input; downloaded results remain wherever you save them.

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