Numerarium is a clean, fast Roman numeral converter supporting bidirectional conversion between Arabic numbers (1-3999) and Roman numerals (I to MMMCMXCIX).
Features:
Instant bidirectional conversion: type in either field, see results in real-time
Conversion history: all conversions are saved locally for reference
Quiz mode: test your knowledge with random Roman numeral questions
Rules reference: complete guide to Roman numeral rules including basic symbols, subtractive notation, and examples
Fully offline: no internet required for core features
No data collection: your privacy is respected