Roman Numeral Converter

Convert numbers to Roman numerals and vice versa

Say Hello to Simplicity

Use this roman numeral converter to change numbers and Roman numerals both ways.

Enter a whole number from 1 to 3999 or a valid Roman numeral.

Click Convert or press Enter to see the answer.

The tool shows the result and a short explanation.

It follows standard Roman numeral rules for clear output.

How It Works

The single input box accepts one value.

For numbers, use digits only.

Range is 1 to 3999.

For Roman numerals, use I V X L C D M.

Uppercase and lowercase both work.

Use standard forms such as IV for 4.

Also use IX for 9 and XL for 40.

You can also use XC for 90.

Use CD for 400.

Use CM for 900.

After conversion you see a line like 42 = XLII.

The second line explains the result in words.

Both lines appear below the button.

Here are the messages you may see.

Keep these notes in mind.

Step-by-Step Instructions

  1. Click the input box.
  2. Type a whole number from 1 to 3999, or a Roman numeral.
  3. Click Convert or press Enter.
  4. Read the bold result line.
  5. Read the explanation line just below.
  6. Change the input and convert again.

Why You’ll Dig This Tool

This roman numeral converter handles both directions with speed and clarity.

Here are common use cases.

Try these sample conversions.

A Little Fun History

Roman numerals use seven letters with set values.

Place a smaller value before a larger one to subtract in set cases.

IV means 4 and IX means 9.

XL means 40 and XC means 90.

CD means 400 and CM means 900.

The converter applies these rules for every result.

It gives the standard form for each number.

Get Started Now

Enter a value and click Convert to begin.

Press Enter if you like keyboard speed.

Keep numbers within 1 to 3999 for the best experience.

Use standard Roman forms for letter input.

That is it.

You are ready to convert.