Roman Numeral Tools
Roman numeral dates.
Turn a birthday, anniversary or any date into Roman numerals, in the order and with the separator you want. Day, month and year are each converted on their own. Runs in your browser.
Convert
Result
Fill the form and press Calculate.
Worked example
For 15 June 1985: day 15 is XV, June is month 6 so VI, and 1985 is M (1000) + CM (900) + LXXX (80) + V (5) = MCMLXXXV. In day-month-year order that is XV.VI.MCMLXXXV. In month-day-year order it is VI.XV.MCMLXXXV. Writing the month as a number first matters: 6/15 and 15/6 are different readings of the same date.
How it works
The day, the month number (January is I, December is XII) and the year are each converted to standard Roman numerals and joined with the separator you pick. Numbers use the letters I, V, X, L, C, D and M, with subtractive pairs such as IV, IX, XL, XC, CD and CM.
Standard Roman numerals stop at 3,999 and have no zero, which is enough for any calendar year from 1 to 3999. The date is checked against the calendar first, including leap years, so 29 February 2023 is rejected. Leap years follow the modern Gregorian rule for every year, including years before 1582.
There is no single official way to write a date in Roman numerals. Dots, dashes, slashes, spaces and bullets are all used; this tool shows all three orders so you can see which one matches the convention you want. If you have a date for a tattoo or engraving, check the order with whoever will read it.
Sources and basis (opened 2026-10-15): Roman numerals - Wikipedia (letter values, subtractive notation and the 3,999 maximum).
FAQ
How do I write a date in Roman numerals?
Convert the day, month number and year separately and join them: 15 June 1985 is XV.VI.MCMLXXXV.
How do I write my birthday in Roman numerals?
Enter the day, month and year, then pick the order. A birth date of 3 March 1990 becomes III.III.MCMXC.
Is there an official format for Roman numeral dates?
No. Separators and the order of day, month and year vary, so pick the one your audience will read correctly.
Can I write a month as a name in Roman numerals?
Months have no Roman-numeral form of their own; the month number is used (March is III).
What is the largest year I can convert?
3999, written MMMCMXCIX. Standard Roman numerals have no way to write 4000 or more without extra notation.
Disclaimer
Check the result before using it in a tattoo, engraving or print order. Order and separators are a matter of convention, not a standard.