Julian Day Number

JDNJD

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The Julian Day Number is a continuous count of days since the beginning of the Julian Period on January 1, 4713 BCE (Julian calendar). It is used primarily in astronomy, chronology, and software to simplify date calculations across different calendar systems. Despite the name, it is unrelated to the Julian calendar.

Used in: International (astronomy, science)

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Gregorian months in 2026

The first day of every Gregorian month, with the Julian Day Number for the same day.

GregorianJulian Day Number
1 January 2026JDN 2461041.5
1 February 2026JDN 2461072.5
1 March 2026JDN 2461100.5
1 April 2026JDN 2461131.5
1 May 2026JDN 2461161.5
1 June 2026JDN 2461192.5
1 July 2026JDN 2461222.5
1 August 2026JDN 2461253.5
1 September 2026JDN 2461284.5
1 October 2026JDN 2461314.5
1 November 2026JDN 2461345.5
1 December 2026JDN 2461375.5

Julian Day Number converters

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