🏛️ 罗马数字日期转换器Roman Numeral Date Converter
把日期转换成罗马数字（如纹身、婚礼请柬常用的 V·XX·MMXX），可选月-日-年、日-月-年或年-月-日顺序和分隔符；也能把罗马数字日期还原为普通日期。Turn a date into Roman numerals — like V·XX·MMXX for tattoos and wedding invitations — in month-day-year, day-month-year or year-month-day order with your choice of separator, or decode a Roman numeral date back to a normal date.
使用说明与常见问题How-to & FAQ
「罗马数字日期转换器」是什么？What is the Roman Numeral Date Converter tool?
把日期转换成罗马数字（如纹身、婚礼请柬常用的 V·XX·MMXX），可选月-日-年、日-月-年或年-月-日顺序和分隔符；也能把罗马数字日期还原为普通日期。Turn a date into Roman numerals — like V·XX·MMXX for tattoos and wedding invitations — in month-day-year, day-month-year or year-month-day order with your choice of separator, or decode a Roman numeral date back to a normal date.
如何使用「罗马数字日期转换器」？How do I use the Roman Numeral Date Converter tool?
在「罗马数字日期转换器」中，填写「方向」、「日期」、「顺序」、「分隔符」、「罗马数字日期」等参数，结果会随输入实时计算并显示在下方。In the Roman Numeral Date Converter: Fill in "Direction", "Date", "Order", "Separator", "Roman numeral date"; results are recalculated instantly as you type.
罗马数字怎么写日期？How is a date written in Roman numerals?
年、月、日分别转换：I = 1，V = 5，X = 10，L = 50，C = 100，D = 500，M = 1000，较小的数写在较大的数左边表示相减（IV = 4，XC = 90）。例如 2020 年 5 月 20 日 = V·XX·MMXX（美式月-日-年）。Convert the year, month and day separately: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000, with a smaller numeral before a larger one meaning subtraction (IV = 4, XC = 90). 20 May 2020 is V·XX·MMXX in US month-day-year order.
为什么只支持到 3999 年？Why only up to 3999?
标准罗马数字没有表示 5000 的符号，最大是 MMMCMXCIX（3999）。Standard Roman numerals have no symbol for 5000, so the largest is MMMCMXCIX (3999).
纹身前要注意什么？Anything to check before a tattoo?
确认日期顺序（美国习惯月-日-年，欧洲多为日-月-年），并检查是否使用规范写法（4 写作 IV 而不是 IIII）。Confirm the order (the US uses month-day-year, Europe mostly day-month-year) and that standard forms are used (4 is IV, not IIII).
罗马数字转日期时可以怎么写？How can I type a Roman numeral date?
大小写、全角字母都可以，各段之间可用 ·、.、-、/、逗号或空格分隔，甚至混用；结果日期按 YYYY-MM-DD 显示（公元 1000 年以前补零，如 0001-01-01）。Upper or lower case and full-width letters all work, and the parts can be separated by ·, ., -, /, commas or spaces, even mixed. The date is shown as YYYY-MM-DD, zero-padded before year 1000 (such as 0001-01-01).
和时区有关吗？Do time zones matter?
无关。「罗马数字日期转换器」只做时长或日期格式的换算，不读取设备时间，时区和夏令时不影响结果。No. The Roman Numeral Date Converter only converts durations or date formats and never reads the device clock, so time zones and daylight saving time do not affect the result.
「罗马数字日期转换器」免费吗？需要注册吗？Is the Roman Numeral Date Converter free? Do I need an account?
「罗马数字日期转换器」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Roman Numeral Date Converter is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.