Excel is not storing exact date. Preserving last day

[uchakula13]

Hi, I am using SheetJs and trying to store date into excel sheet. I noticed the date records are storing incorrectly, Ex - when i try to store 04-05-2022 , it is storing 04-04-2022. It is missing 1 day and storing previous date. Am using latest version 0.18.5 . Please advise

[reviewher]

Can you share an example file and your system timezone?

[chacabuk]

This is an old issue...

Is not one day left, ist just a few seconds left For example 20/12/2021 00:00:00 is export as 19/12/2021 23:59:12

My timezone is -3

a simple example to reproduce:

    const exportData = [
      { date: new Date('2021/12/20 00:00:00'), name: 'Peter' },
      { date: new Date('2021/12/30 18:30:00'), name: 'Jhon' },
    ]

    const wb: XLSX.WorkBook = XLSX.utils.book_new();
    const ws: XLSX.WorkSheet = XLSX.utils.json_to_sheet(exportData, { dateNF: 'dd/mm/yyyy HH:mm:ss' });

    ws['!cols'] = [{ wch: 30 }, { wch: 30 }];

    XLSX.utils.book_append_sheet(wb, ws, 'Data');
    XLSX.writeFile(wb, 'data.xlsx');

date	name
19/12/2021 23:59:12	Peter
30/12/2021 18:29:12	Jhon

[SheetJSDev]

Atlantic/Azores h/t @ruitalia . The timezone had fractional offset -1:42:40 in 1900

[mrichard95]

I'm also using version 0.18.5 and see the same issue in India Standard Time zone. It looks like 10 seconds is being subtracted off of the time.

Date in Excel File: 7/5/2023

Result after XLSX.read: { "t": "d", "v": "2023-07-04T18:29:50.000Z", "z": "m/d/yy" }