Greek numeral converter

Enter an integer from one to nine thousand nine hundred ninety-nine with direction to_greek to receive a canonical string such as alpha with right keraia for one, iota-beta with right keraia for twelve, or left-keraia beta kappa delta with right keraia for two thousand twenty-four. Switch direction to from_greek to parse a Greek numeral string—with or without keraia—and recover the Arabic integer.

What Ionic Greek numerals are and what the response contains

This calculator returns the original value echo, the normalized direction, the Arabic integer, the canonical Greek string with keraia, a boolean keraia flag, the method tag ionic_greek_numerals, a short formula reminder of the place alphabet, and the supported min_n and max_n bounds. There is no approximate OCR path and no silent coercion of Latin look-alikes into Greek letters: the engine either builds an exact integer inside one through nine thousand nine hundred ninety-nine or rejects the input with invalid_input. Rejected cases include missing value or direction, zero and negatives, values above the ceiling, non-numeral characters, repeated place letters, a left keraia without a thousands digit, and a number typed when direction is from_greek.

How value and direction are read and how results stay reproducible

When converting to Greek, value must be a whole integer from one to nine thousand nine hundred ninety-nine as a number or a decimal digit string; floats, empty strings, and out-of-range magnitudes fail with a clear message. When converting from Greek, value must be a string of Greek numeral letters and optional keraia: outer whitespace is trimmed, uppercase is folded, stigma digraph sigma-tau is accepted as six, and ASCII apostrophes are treated as right keraia because Unicode NFKC often rewrites the official numeral sign into a modifier prime. Parsing walks left keraia plus unit letter for thousands, then allows each of hundreds, tens, and units at most once so malformed stacks cannot invent a second hundreds digit. The preferred fields are value for the payload and direction for the conversion sense, but aliases n, number, text, input, and numeral for value, and dir, mode, and to for direction, are accepted so spreadsheets, query strings, and typed forms can reuse the same contract. Direction must resolve to to_greek or from_greek; convenient aliases such as encode, greek, decode, and arabic are folded into those two modes. Successful parses re-encode through the same to_greek table, so output always uses canonical stigma, koppa, sampi, and both keraia marks even if the input omitted them. Pair the free browser run on this page with the priced API when you need the identical conversion inside an automated pipeline without re-implementing the Ionic alphabet yourself.

Where Greek numeral conversion fits in study, cataloging, and software

On this page the work runs entirely in your browser; through the API each successful lookup costs $0.002, failed validation is not charged, and nothing is stored after the response returns. That split—free interactive exploration and a priced, identical API—matches the rest of the KIT tier-A catalog and lets you move from a classroom demo to an automated pipeline without changing the mathematical result.