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Ubify Core Engineering Team
SOFTWARE ENGINEERS & SYSTEMS ARCHITECTS
About This Tool
This bidirectional conversion utility translates numbers between Arabic decimal integers and classical Roman numerals in real time. It supports the standard subtractive Roman numeral range from 1 to 3999. Entering either format immediately updates the opposite field in your browser.
### Roman Numeral Subtractive Notation The conversion uses standard additive and subtractive symbols defined by classical Latin conventions:
- **Single Symbols:** $\text{I} = 1$, $\text{V} = 5$, $\text{X} = 10$, $\text{L} = 50$, $\text{C} = 100$, $\text{D} = 500$, $\text{M} = 1000$. - **Subtractive Pairs:** Subtractive pairs represent values preceding a higher unit: - $\text{IV} = 4$, $\text{IX} = 9$ - $\text{XL} = 40$, $\text{XC} = 90$ - $\text{CD} = 400$, $\text{CM} = 900$ - **Range Constraint:** Classical Roman notation without vinculum horizontal overlines is traditionally bounded between 1 and 3999 (`MMMCMXCIX`). Values outside this range display an input boundary prompt.
### Concrete Conversion Examples - **Modern Calendar Year:** $2026 = 1000 + 1000 + 10 + 10 + 5 + 1 = \text{MMXXVI}$. - **Historic Date:** $1984 = 1000 + (1000 - 100) + (100 - 20) + (5 - 1) = \text{MCMLXXXIV}$. - **Century Milestone:** $499 = (500 - 100) + (100 - 10) + (10 - 1) = \text{CDXCIX}$.
### Privacy and Client-Side Execution All symbol parsing and integer arithmetic evaluate directly within local JavaScript memory. No numeric inputs or translation requests are sent to remote servers.
How to Use
- 1
Enter an Arabic integer (1 to 3999) in the decimal field to generate its Roman numeral equivalent.
- 2
Alternatively, type standard Roman numeral characters (e.g. MMXXVI) in the Roman field to decode the integer value.
- 3
Copy the converted result directly using your keyboard or clipboard.
Frequently Asked Questions
Why does the converter cap decimal inputs at 3999?
Standard typographic Roman numerals lack single-character representations for numbers of 4000 or greater without vinculum overline bars (which denote multiplication by 1000).
Does the parser accept lowercase Roman characters like mmxxvi?
Yes. The input parser normalizes letter inputs to uppercase before decoding character values.
Are any numbers sent over the internet?
No. The conversion executes entirely on your device using client-side JavaScript.