A Roman numeral converter that explains itself, offline and in your own language.
Why does the app refuse IIII when my watch has it on the dial?
Because a clock dial is not a numeral system. Four is IV in Roman notation, but almost every clock ever made prints IIII instead — for balance against the VIII opposite it, and because the tradition is older than the subtractive rule. The app converts strictly and shows the dial form separately on the Learn tab, labelled for what it is.
It says my numeral is not in order. What does that mean?
Roman numerals only subtract in six places: IV, IX, XL, XC, CD and CM. IL for 49 and IC for 99 look reasonable and are not numerals — 49 is XLIX. When the app rejects something it names the rule broken rather than just saying invalid, because most of the people typing a wrong numeral are trying to learn the right one.
How do I write a number bigger than 3,999?
Standard notation stops at MMMCMXCIX. Above that a bar over a numeral multiplies it by a thousand, so 4,000 is IV with a bar. The older apostrophus form writes 1,000 as CIƆ. Both are on the Learn tab, up to 3,999,999.
Can I type in my own numerals?
Yes. The number field accepts Arabic-Indic, Persian, Devanagari, Bengali, Gurmukhi, Tamil, Telugu, Thai and fullwidth digits as well as ASCII ones, and the numeral field accepts both plain letters and the precomposed Unicode numeral characters some keyboards produce.
Does it work without internet?
Yes, entirely. The app never connects to the internet and stores nothing about you.
Email quicksupport36@gmail.com and describe what happened. Including your device model and iOS version helps.
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