Roman Numeral Converter

Convert numbers to Roman numerals and back with strict canonical validation and symbol breakdowns.

MMXXVI
2026

Canonical form — round-trips exactly.

Symbol table
M = 1000CM = 900D = 500CD = 400C = 100XC = 90L = 50XL = 40X = 10IX = 9V = 5IV = 4I = 1

Classic notation covers 1–3999 (a bar over a numeral for thousands beyond that is not handled here). Subtractive pairs (IV, IX, XL…) are enforced on the Roman-input side.

About Roman Numeral Converter

Convert numbers to Roman numerals and back with strict canonical validation and symbol breakdowns.

As a Conversion tool, Roman Numeral Converter converts between units instantly — type a value, pick the source and target units, and the result updates live as you type, so you never have to do the math by hand.

How to Use Roman Numeral Converter

  1. Enter the value you want to convert in the input field.
  2. Select the source unit and the target unit.
  3. Read the result instantly — it updates live as you type.
  4. Copy the output or swap the units to convert in the other direction.

Key Features

  • Live two-way conversion — edit either side and both update together.
  • Uses standard, precise conversion factors for everyday and technical use.
  • Runs entirely in your browser — works offline and sends nothing anywhere.

Frequently Asked Questions

How accurate are the conversions from Roman Numeral Converter?

Conversions use standard published factors, and rounding happens only at display time. Results are precise enough for everyday, academic and engineering use.

Is Roman Numeral Converter free to use?

Yes. Roman Numeral Converter is completely free with unlimited use — no account, download or payment required.

Is my data uploaded to a server?

No. Roman Numeral Converter runs entirely in your browser. Your inputs are never sent to our servers or stored anywhere.

Does Roman Numeral Converter work on mobile?

Yes. The interface is fully responsive and works in any modern browser on Android, iPhone, tablets and desktops.

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