Minguo ROC to Gregorian date converter

Enter the Minguo year, month, and day in year-MM-DD form, such as 113-07-25. The converter adds 1911 to the year, preserves the month and day, and checks that the resulting Gregorian date is real, including the correct leap-year rule. The response includes both complete dates and their individual numeric parts for straightforward use in records and integrations.

Enter an unambiguous Minguo calendar date

Provide the date as a positive Minguo year followed by a two-digit month and a two-digit day, separated by hyphens. For example, 113-07-25 identifies year 113 of the Republic of China calendar, month 07, and day 25. The year does not need leading zeroes, but the month and day do because a fixed structure prevents ambiguous readings. This capability intentionally accepts a complete date rather than a bare year, a date written with slashes, or text containing a localized era label. That narrow contract makes automated imports predictable and makes malformed source data visible instead of guessing what the sender intended. Minguo year 1 corresponds to Gregorian 1912, so the accepted calendar begins with positive Minguo years. Before converting, the tool confirms that the month is from 01 through 12 and that the day exists in that month. A missing field, year zero, extra whitespace, or a differently arranged date is reported as invalid input for correction at the source.

Understand the conversion and validation

The conversion uses the civil-calendar relationship Gregorian year equals Minguo year plus 1911. Only the year changes; the numeric month and day remain the same. Thus Minguo 113-07-25 becomes Gregorian 2024-07-25. The calculation uses integer arithmetic and does not construct a JavaScript Date object. That detail matters because Date parsing can interpret text differently across environments or apply a local timezone near midnight. Here, the same input produces the same output in a browser, a server process, or an automated test. Calendar validation is applied to the resulting Gregorian year. Months with thirty days reject day 31, February rejects dates beyond its actual length, and February 29 is accepted only when the converted Gregorian year satisfies the divisible-by-4, century, and divisible-by-400 rules. The result contains normalized complete Minguo and Gregorian date strings as well as numeric year, month, and day fields, making it suitable for display or structured downstream processing without reparsing the output.

Use the result safely in records and workflows

This converter is useful when a Taiwanese document, government form, invoice, certificate, or database export stores a date with a Minguo year while another system expects a Gregorian date. Keep the original Minguo value beside the converted value when auditability matters; the paired response makes that easy and preserves a clear trail back to the source. For batch work, call the capability once per item and treat an invalid-input response as a data-quality issue that needs review rather than silently substituting a guessed date. The tool performs a calendar conversion only. It does not infer whether a two- or three-digit number came from the Minguo calendar, interpret Chinese era characters, translate lunar-calendar dates, or attach a time of day. It also does not shift the date for a timezone, because a civil calendar date has no clock offset by itself. Browser use is available for quick individual checks, while API execution costs $0.002 per request and provides the same deterministic calculation for integrations.