Software for astronomy, calendars and date conversion

BCE‑BC‑AD‑CE Converter

Celtic Festivals and Cross Quarter Dates

Chinese Calendrics

Date‑Time Calculator

Easy Date Converter

Eclipses, Moon Phases and Seasons

Equinoxes, Solstices and Cross‑Quarter Days

Julian‑Gregorian‑Dee Date Calculator

Lunar Calendars and Eclipse Finder

For each program, clicking on the Purchase button takes you to a page where you can purchase a user license which is valid perpetually or (at half‑price) for just 3 months. You can pay via credit card or via a Western Union money transfer agent.

BCE‑BC‑AD‑CE Converter 2.24 Click on the title for the full description Prices before* sale discount:* US$22.45, €21.25 or £18.25 for a perpetual license or US$7.45, €6.95 or £5.95 for a 3-month license
Converts between calendar dates in BCE, BC, AD and CE date formats, and adds/subtracts a number of days, weeks, months and years to/from a given date. Read more ...

Celtic Festivals and Cross Quarter Dates 9.54 Click on the title for the full description Prices before* sale discount:* US$29.95, €28.25 or £24.45 for a perpetual license or US$9.95, €9.45 or £8.25 for a 3-month license
A program to find the exact dates and times, and zodiac positions, of full moons and dark moons, lunar Celtic festivals (Imbolc, Beltane, Lughnasadh and Samhain), equinoxes and solstices, and solar cross-quarter days. Moreover, it can do this for any range of years between 1600 and 2099. Read more ... Top

Chinese Calendrics 17.07 Click on the title for the full description Prices before* sale discount:* US$59.95, €56.75 or £48.75 for a perpetual license or US$19.95, €18.95 or £16.25 for a 3-month license
A program for the scholarly study of the Chinese Calendar. It convert between dates in various Chinese calendars and dates in the Gregorian and Julian calendars, and finds lunar new year's day and leap months for any year in the Chinese Calendar. Read more ... Top

Date‑Time Calculator 6.04 Click on the title for the full description Prices before* sale discount:* US$39.95, €37.75 or £32.45 for a perpetual license or US$13.25, €12.45 or £10.75 for a 3-month license
Software to perform conversion, addition and subtraction of dates and times. Read more ... Top

Easy Date Converter 12.57 Click on the title for the full description Prices before* sale discount:* US$39.95, €37.25 or £32.45 for a perpetual license or US$13.25, €12.45 or £10.75 for a 3-month license
Adds a number of days or months to a date, calculates the number of days between two dates (with or without weekend days), and converts among Common Era (Gregorian) dates, Julian dates, ISO 8601 Week dates, Hermetic Leap Week dates, Julian day numbers and day-in-year dates of the form yyyy-ddd. Bilingual: English and German Read more ... Top

Eclipses, Moon Phases and Seasons 8.14 Click on the title for the full description Prices before* sale discount:* US$39.95, €37.75 or £32.45 for a perpetual license or US$13.25, €12.45 or £10.75 for a 3-month license
Displays (over a range of years) the exact dates and times of partial, annular and total solar eclipses, of partial, penumbral and total lunar eclipses, of phases of the Moon, and of solstices, equinoxes and the solar cross-quarter days. Read more ... Top

Equinoxes, Solstices and Cross‑Quarter Days 6.27 Click on the title for the full description Prices before* sale discount:* US$19.95, €0.95 or £0.95 for a perpetual license or US$6.75, €0.25 or £0.25 for a 3-month license
Software to calculate accurate dates and times for equinoxes, solstices and the Celtic cross-quarter days. The cross-quarter days are those midway between the equinoxes and solstices. Works for both the northern hemisphere and the southern. Read more ... Top

Julian‑Gregorian‑Dee Date Calculator 7.54 Click on the title for the full description Prices before* sale discount:* US$29.95, €28.45 or £24.45 for a perpetual license or US$9.95, €9.45 or £8.25 for a 3-month license
Converts between Julian, Gregorian, Dee and Dee-Cecil calendar dates in various formats, does date arithmetic, and calculates northern spring equinoxes using either mean or apparent solar time. Read more ... Top

Lunar Calendars and Eclipse Finder 17.17 Click on the title for the full description Prices before* sale discount:* US$29.95, €28.45 or £24.45 for a perpetual license or US$9.95, €9.45 or £8.25 for a 3-month license
A program to search for eclipses (lunar, solar, total, annular and partial), to calculate the phase of the Moon at any given date and time and to convert between dates in the Gregorian and Julian calendars and dates in various lunar calendars: Meyer-Palmen Solilunar, Hermetic Lunar Week, etc. Read more ... Top

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