Lew's Julian Date Calculator

A One Cell Excel Spreadsheet JD Formula

This new spreadsheet is in the very first days of use. Only a few numbers have been tested through it and there may be unknown bugs! Use it with caution, verifying results.

If you use it and find any problems (incorrect answers, difficulty using it) please send Lew an immediate E-mail at

The code is a single cell MS Excel expression which will take the (UT) date written in the (pseudo-VSNet) format:



and converts it into JD using Meeus' method. It can be copied and pasted into each cell in a column to the immediate right of a column of dates and it will produce the JD of the (AD) date in it. If the data is in the form yymmdd.dd, you've got to add the preceeding 19 (or 20, or 18).

Or you can use it as a single cell and write a macro to calculate a column of numbers.

It is available here as a protected spreadsheet with instructions :

The spreadsheet is protected against accidental erasure but the details of the calculations are presented, as are tips in using it. There are NO error checks. If you enter the 35th of February, you will get an answer. If you input bad data, you will get bad answers. GIGO applies here. All Entries MUST be 8 digits BEFORE the decimal point.

You should not get a warning that the spreadsheet contains Macros. There are no Macros associated with it even though it is protected against accidental erasure. You may copy the cell into your spreadsheets this for your own calculations.

It is available at the link below (just click on it and it will begin by launching Excel). The B1 cell may be copied from the sheet directly into another spreadsheet.