Conversion and verification
Check a date or time period quickly without reproducing a complex calendar calculation by hand.
Dates & time
Coptic ↔ Gregorian Date Converter
Bidirectional Coptic and Gregorian date converter with support for the short thirteenth month, Nasie.
Coptic ↔ Gregorian Date Converter
Convert a date between the Gregorian calendar and the thirteen-month Coptic calendar used for many Coptic cultural and liturgical date references.
The Coptic calendar has 13 months; Nasie is a short month at the end of the year.
Result
Calendar conversion is calculated locally. For liturgical or official use, check the convention used by your reference source.
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How does this tool work?
Convert a date between the Gregorian calendar and the thirteen-month Coptic calendar used for many Coptic cultural and liturgical date references.
Gregorian to Coptic conversion uses the browser’s Intl coptic calendar support to extract the matching Coptic year, month and day. For the reverse direction, Bethemesh searches for the exact Gregorian date that produces the entered Coptic values. The calendar contains twelve months of thirty days plus a short thirteenth month, Nasie, whose length changes with the calendar year.
How to use this tool
Enter the inputs
Provide the date, location or numerical values requested by the tool.
Choose the context
Select the conversion direction or local context whenever the calculation requires it.
Read and verify
Review the result, then change the inputs to compare another date or location.
Use cases
Practical planning
Prepare travel, documents, photography or observations with a precise time reference.
Calendar comparison
Compare two dating systems or two ways of dividing time from the same civil day.
Tips and best practices
- Check the time zone whenever the result depends on the Sun.
- For historical or administrative use, consider the conventions that applied in the relevant country and period.
- Calculations run locally in the browser and can be repeated immediately.
Frequently asked questions
Is the calculation sent to a server?
No. The calculation engine runs directly in your browser, so the values used by the tool are processed locally.
Can I convert or calculate several dates?
Yes. Change the fields and run the calculation again as many times as needed without reloading the page.
Can the result differ from an official source?
Yes. Some traditions, calendar reforms or local conventions use different rules, so an official source should be checked for legal or ceremonial use.
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