# Roman numeral converter

> Translate canonical Roman numerals and whole numbers.

[Open tool](https://www.toolcabana.com/su/roman-numerals) · [Units and measurement](https://www.toolcabana.com/su/category/units-and-measurement)

Tool ID: roman-numerals. Requested language: su. Description language: en. Complete guide translation: no; untranslated sections use English.

## Overview (en)

The Roman numeral converter turns a whole number from 1 to 3999 into Roman numerals, or, with Roman to decimal switched on, reads Roman numerals back as a number. It writes subtractive forms such as IV, IX, XL, XC, CD and CM, and when decoding it only accepts canonical numerals, rejecting forms such as IIII or IC.

## Supported tasks (en)

Translate canonical Roman numerals and whole numbers.

## Steps (en)

1. Type or paste your source, or load an example.
2. Change the basic settings or open Advanced mode to fine-tune the result.
3. Review and copy or download your result. Pause Live results to run manually. Sources or individual settings above 20,000 characters require an explicit run.

## Settings

- Roman to decimal (en; key: decode; type: checkbox)

## Limitations (en)

Text operations generally accept up to 2,000,000 characters. Individual parsers, generators and formulas apply additional limits shown by their controls.

## Example input

```text
2026
```

## Privacy and connections (en)

This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.

## Questions (en)

### How do you write 2026 in Roman numerals?

2026 is MMXXVI: two thousands (MM), two tens (XX), a five (V) and a one (I). The converter builds numerals from the largest value down, using M, CM, D, CD, C, XC, L, XL, X, IX, V, IV and I.

### What is the largest number I can convert to Roman numerals?

The converter accepts whole numbers from 1 to 3999, which is MMMCMXCIX. Zero, negative numbers, fractions and values of 4000 or more are rejected because standard Roman numerals have no symbol for them.

### Why is IIII rejected when converting Roman numerals to numbers?

The decoder checks that your input matches the canonical form it would produce for the same value. IIII would equal 4, but the canonical form is IV, so the tool reports that the numeral is not in canonical form.

### Where is my input processed?

This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.

### What are the input limits?

Text operations generally accept up to 2,000,000 characters. Individual parsers, generators and formulas apply additional limits shown by their controls.

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