Roman Numeral Converter Online — Free & Private

A free edge API by formatho.com, privacy-first developer tools.

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Free, no signup, runs entirely in your browser — your data never leaves your device.

🔓 Free🔒 Zero tracking🚫 No data collection⚡ Edge-fast

Usage

# number → Roman
curl "https://roman-numeral-formatho.filesformatho.workers.dev/api?number=2026"
# Roman → number
curl "https://roman-numeral-formatho.filesformatho.workers.dev/api?roman=MMXXVI"

Provide one or both parameters — validation is strict canonical subtractive notation (1–3,999; non-standard forms like IIII are rejected).

Full parameter reference: /api endpoint.

Privacy-first: values are converted in-memory at the edge and never logged or stored.

Full browser tool

Convert Roman numerals entirely client-side: Roman Numerals Converter on formatho.com.

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