Scripts & numerals

Digits, writing systems and transliteration, converted losslessly.

Written for: People moving text between systems · Students and language learners

What this family is for

Digits are not universal. A number copied from a Thai invoice, an Arabic-Indic spreadsheet or a Devanagari schoolbook arrives as different characters, and any system that expects 0–9 will reject it or silently misread it. These tools convert between numeral systems without loss, romanise non-Latin scripts so they can be searched and pronounced, and normalise mixed text back to a single form.

Numeral systems, Roman numerals and number words

These tools all deal with representing a number, but for different purposes. The numeral-system converter maps between the digit glyphs of 22 scripts — Thai ๑๒๓, Arabic-Indic ١٢٣, Devanagari १२३ — and is about the shape of the digits, not the value. Roman numerals and Chinese numerals are different number systems entirely, with their own rules for magnitude and subtraction. Number-to-words is the written-out English form.

The distinction that matters: converting 123 to Thai digits gives ๑๒๓, which reads as 123 to a Thai reader. Converting 123 to Roman gives CXXIII, which is a different notation with a different set of legal values. They are not interchangeable operations.

If you have…	Use	Because
The same number in another script's digits	Numeral system converter	Digit glyphs map one-to-one; the value is unchanged
A number in the classical Roman notation	Roman numerals	A separate system with canonical-form rules
A number written in Chinese characters	Chinese numerals	Grouping is in 10,000s, and financial forms use different characters
A number spelled out in English words	Number to words	Useful for cheques, legal text and accessibility

7 tools in Scripts & numerals

Common mistakes with these tools

• Assuming every script uses the same digit order — Most decimal scripts map 0–9 to ten consecutive code points, but the glyph for 5 is not always the fifth character as you read it. The converter uses the Unicode digit blocks.
• Treating Roman numerals as arithmetic — IIII is 4 arithmetically but not a canonical Roman numeral. The parser round-trips to reject non-canonical forms rather than silently accepting them.
• Expecting Chinese grouping to match English — Chinese groups by 10,000 (万), not 1,000. A direct digit-by-digit substitution produces the wrong unit boundaries.
• Relying on Roman numerals above 3,999 — The standard form has no symbol beyond M repeated three times. Larger values need a vinculum, which is not universally understood and is not produced here.

Frequently asked questions

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