Roman Numeral Converter
Text & Code · Free Online Tool
Convert between Roman numerals and Arabic numbers.
Roman Numeral Reference
Bidirectional
Type an Arabic number to get a Roman numeral, or type Roman to get the number — instantly.
Validated
Roman numerals are validated against standard rules, supporting values from 1 to 3999.
Private
Conversion runs entirely in your browser. Nothing is sent to a server.
How to Use Roman Numeral Converter
- 1Enter or paste your text or code into the input area.
- 2Choose the desired operation (format, convert, analyze, etc.).
- 3Click the action button to process.
- 4Copy the result from the output area.
Features
- ✓100% free — no signup, no subscription, no ads
- ✓Runs entirely in your browser — data never leaves your device
- ✓Fast and lightweight — instant results
- ✓Cross-platform — works on desktop, tablet, and mobile
Frequently Asked Questions
Can I format code in different styles?
Yes, the SQL Formatter and other code tools support multiple formatting options and indentation styles.
Is regex testing case-sensitive?
The Regex Tester supports case-sensitive and case-insensitive matching, along with global and multiline flags.
Can I process multiple lines at once?
Yes. Most text tools operate on the whole input, so you can paste multi-line content and apply the operation to every line in a single pass.
Is there a character limit?
There is no fixed limit — the tools run in your browser, so the practical ceiling is your device memory. Very large inputs may slow down rendering.
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