Serial Number To Date Converter
Microsoft Excel uses a date system where dates are recorded as the number of days from the start of year 1900 (1 => 1900-01-01) or 1904 (1 => 1904-01-02). Excel typically displays dates correctly but sometimes you may encounter underlying date serial numbers.
The easiest way to convert Excel date serial numbers to dates is by pasting them into Excel and changing the format to "Short Date" or "Long Date" in the Home ribbon.
Alternatively, use the form below to enter one or more Excel date serial numbers (one per row) and click Convert.
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Please note that this service is provided without warranty or support. I am not responsible for any damages or inaccuracies that may arise from the outputs or the use of this service.
More Information
- Enter each serial number on a separate row.
- You can input a maximum of 1 million values.
- The values must be between 1 and 1,000,000. I.e., dates after 1900 or 1904.
- The function assumes that serial numbers are "Short Dates" rather than "Long Dates" (represented by decimal numerals). It will automatically remove spaces, commas, and full stops, and concatenate the numbers. Ability to convert to Long Dates is still being developed.
- Empty rows will result in empty rows in the output.
- The function uses the 1900 system by default, which is also the default in Excel. Check the dating version used in your source system using the instructions in the link above.
- Excel assumes that 1900 was a leap year, although it wasn't. Please be aware of this quirk.
- The output dates are formatted as YYYY-MM-DD. Excel should automatically recognise the dates when pasting value into a sheet.
YYYY-MM-DD