JDN Calculator

About This Tool

The JDN Calculator is a comprehensive online tool designed for precise conversion between Gregorian dates and Julian Day Numbers. Whether you're an astronomer needing to calculate celestial event timings, a historian working with historical dates, or a developer implementing date algorithms, this tool is tailored to your needs. It supports two main functions: converting a selected Gregorian date into a Julian Day Number, and reversing the process to obtain a Gregorian date from a given JDN. The interface allows users to specify the date type, enter valid date components, or input a JDN directly. Optional calendar system selection between Gregorian and Julian calendars provides historic accuracy. The calculator handles leap years, fractional days, and validates input data to ensure reliable conversions. Result outputs are displayed clearly, with options for copying, exporting, or viewing within the interface. The tool is optimized for both desktop and mobile devices, featuring a clean, accessible design. Advanced features include conversion history, language support, and result export options, making it a versatile asset for scientific research, educational lessons, or software development projects.

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