Excel serial date to real date

Days since the 1900 date system's zero; the fraction is the time of day, read as UTC.

Excel stores dates as serial numbers: days since its 1900 epoch, with the time of day as a fraction. 45261.75 is December 1, 2023 at 18:00. If a spreadsheet ever handed you a five-digit number where a date should be, that's what it is. Paste one below to convert it, fraction and all. The same encoding appears as OADate in .NET and in many CSV exports.

Detected: Excel serial date

Your timezone

UTC · GMT+00:00 · UTC

Fri, Dec 01, 2023, 12:00:00 AM

Common formats

UTC

Fri, Dec 01, 2023, 12:00:00 AM

ISO 8601

2023-12-01T00:00:00.000Z

Unix (seconds)

1701388800

Unix (millis)

1701388800000

Relative

World clock

Los Angeles PST

Thu, Nov 30, 2023, 04:00:00 PM

GMT-08:00

Chicago CST

Thu, Nov 30, 2023, 06:00:00 PM

GMT-06:00

New York EST

Thu, Nov 30, 2023, 07:00:00 PM

GMT-05:00

London GMT

Fri, Dec 01, 2023, 12:00:00 AM

GMT+00:00

Paris CET

Fri, Dec 01, 2023, 01:00:00 AM

GMT+01:00

Kolkata IST

Fri, Dec 01, 2023, 05:30:00 AM

GMT+05:30

Shanghai CST

Fri, Dec 01, 2023, 08:00:00 AM

GMT+08:00

Tokyo JST

Fri, Dec 01, 2023, 09:00:00 AM

GMT+09:00

Sydney AEDT

Fri, Dec 01, 2023, 11:00:00 AM

GMT+11:00

Do it with the API

curl https://parsetime.dev/api/t/45261?format=excel

The same conversion as JSON: no key, no signup, permissive CORS. Try this call or read the API docs.

Common questions

Why does Excel show a number like 45261 instead of a date?
The cell is formatted as a number rather than a date, but the underlying value is the same either way: days since the 1900 epoch. Paste the number above to see which date it is, or reformat the cell in Excel.
How do I convert an Excel serial number to a date by formula?
In Excel itself, just format the cell as a date. To do it arithmetically: the Unix timestamp is (serial − 25569) × 86400, because 25569 is the serial for January 1, 1970.
What is the 1900 leap-year bug?
Excel treats 1900 as a leap year (it wasn't) to stay compatible with Lotus 1-2-3. Serial 60 is the nonexistent February 29, 1900, so serials below 61 are one day off. Values from March 1900 onward are unaffected.
What about the 1904 date system?
Old Mac versions of Excel counted from January 1, 1904 instead. If a converted date is exactly 1,462 days off, the file uses the 1904 system. Add 1462 to the serial and convert again.

Related converters