Roman Numeral Converter

Convert numbers to Roman numerals and back, and turn any date into Roman numerals for tattoos, certificates, logos and design work.

The Roman Numeral Converter turns ordinary numbers into Roman numerals and converts them back again, plus it can convert an entire date into Roman numerals for use on tattoos, certificates, wedding invitations, logos and monument-style designs. Enter a number up to 3999 or a full date, and the converter handles the numeral construction rules — including subtractive notation like IV for 4 — automatically.

Because Roman numerals follow specific combination rules rather than a simple digit-by-digit substitution, manually converting larger or more awkward numbers is error-prone. This tool removes that risk, instantly showing the correct numeral for any valid input, or decoding an existing Roman numeral back into its numeric value for verification.

How to use the Roman Numeral Converter

1. Enter a whole number between 1 and 3999 to convert it to Roman numerals.
2. Or enter an existing Roman numeral to convert it back into a standard number.
3. Switch to the date mode and select a day, month and year to convert an entire date.
4. Review the resulting Roman numeral output for the date, shown as separate converted components.
5. Copy the result for use in a design, tattoo reference or document.

Why use this tool

Handles subtractive notation correctly

Rules like IV for 4 and IX for 9 are applied automatically, avoiding the common manual mistake of writing IIII instead of the correct subtractive form.

Date conversion built in

A full date can be converted into Roman numerals with day, month and year handled as separate components, matching the format commonly used for tattoos and monument inscriptions.

Bidirectional conversion

Numbers can be converted to Roman numerals and existing Roman numerals converted back to standard numbers, useful both for creating new numerals and verifying ones you've already seen.

Common use cases

• Converting a birth year or anniversary date into Roman numerals for a tattoo design.
• Creating a Roman numeral date for a wedding invitation or save-the-date card.
• Checking the numeric value of a Roman numeral seen on a building cornerstone or old document.
• Formatting a movie or edition number in Roman numerals for a title design.
• Converting a graduation year into Roman numerals for a class ring or certificate.

Maximum supported value

Standard Roman numerals support values up to 3999, written as MMMCMXCIX. Numbers beyond this require an overline notation to indicate multiplication by 1000, which falls outside standard everyday usage and isn't handled by this tool.

Converting a full date

Using the date field converts the day, month and year separately into their own Roman numeral components, which is the format seen on tattoos and monument inscriptions rather than converting the date as one combined number.

Common numeral combinations

Numerals follow additive and subtractive rules: values are built by combining symbols like I, V, X, L, C, D and M, with a smaller symbol placed before a larger one to subtract, such as IX for 9 or XL for 40. Understanding this makes it easier to sanity-check a converted result at a glance.

Frequently asked questions

What is the largest number supported?

3999 (MMMCMXCIX). Standard Roman numerals have no symbol for larger values without overline notation.

How do I write a date in Roman numerals?

Use the date field: the day, month and year are each converted separately, which is the format used for tattoos and monument inscriptions.

Is Roman Numeral Converter free to use?

Yes. Roman Numeral Converter on Klipza is completely free with no account, no subscription and no watermark on your files, and there is no daily usage limit.

Are my files safe when using Roman Numeral Converter?

Processing happens locally in your browser wherever technically possible, so your files are not uploaded to a server, stored or shared with third parties.

Does Roman Numeral Converter work on mobile phones?

Yes. It is fully responsive and runs in any modern browser on Android, iPhone, iPad, Windows and macOS — nothing to install.