Roman Numeral Converter
Convert whole numbers from 1 to 3999 into Roman numerals or validate and decode canonical Roman numeral text.
Start with your input
Edit the example or replace it with your own text.
Choose your options
These settings are optional. Keep the defaults to get started.
How to use Roman Numeral Converter
- Load the example or enter your own values.
- Choose the relevant options and run the tool.
- Review the result, then copy it or download a local file.
When this tool is useful
Convert a year, outline label or edition number into standard Roman numerals without manually combining symbols. Choose the direction before entering either a decimal integer or a Roman numeral. The reverse conversion accepts lowercase input and normalizes it to uppercase, then checks that the spelling follows the usual subtractive forms such as IV, IX, XL and CM.
Reading the result and limitations
The supported range is one through 3999, using the symbols I, V, X, L, C, D and M. Zero, negative values, fractions, overlines and historical additive variants are outside this tool. Noncanonical strings such as IIII or IC are rejected rather than assigned a guessed meaning. The JSON result includes both representations so you can inspect the conversion before copying it into a document.
Example input
2026
What are the main limits of Roman Numeral Converter?
The supported range is one through 3999, using the symbols I, V, X, L, C, D and M. Zero, negative values, fractions, overlines and historical additive variants are outside this tool. Noncanonical strings such as IIII or IC are rejected rather than assigned a guessed meaning. The JSON result includes both representations so you can inspect the conversion before copying it into a document.
Is input uploaded?
Processing takes place in your browser. This tool does not send your input or selected files to a conversion API.