Foundry Roman Numeral Converter

Use this endpoint whenever you need a reliable, bidirectional Roman numeral conversion for any integer from 1 to 3999. It handles both directions (number→Roman and Roman→number) in a single call with a simple string input, making it ideal for labeling, design, historical date formatting, or educational tools without needing to implement the conversion logic yourself.

• Input integer out of range (below 1 or above 3999) returns an error
• Malformed or invalid Roman numeral string returns an error
• Empty or missing input field returns a validation error
• Non-numeric string passed as a number causes a parse error