Kana-Rōmaji Mapping Lookup

Apply longest-match caller kana-to-romaji mappings with unmatched text/indices retained, avoiding invented Hepburn/Kunrei/assimilation choices; dictionary coverage and contextual sokuon/long-vowel rules remain caller responsibility.

Description

Kana romanization depends on dictionary coverage and contextual conventions.

Kana romanization depends on dictionary coverage and contextual conventions. A caller-supplied longest-match mapping makes its choices explicit.^[1]

Enter text and aligned nonempty unique kana patterns1–8 characters with Roman values 1–32 ASCII letters/apostrophes/hyphens. Return transformed text, pattern count and unmatched source code-point indices.

When to use Kana-Rōmaji Mapping Lookup

Use Kana-Rōmaji Mapping Lookup when you need to evaluate the supplied records under the calculation and evidence rules below. No Hepburn/Kunrei, sokuon, assimilation or long-vowel rule is invented; include needed sequences in the mapping.

Prepare explicit text tokens, annotated language observations, caller mappings or a supported locale as requested. Preserve source evidence and the stated Unicode counting convention.

How to use Kana-Rōmaji Mapping Lookup and understand its results

Prepare explicit text tokens, annotated language observations, caller mappings or a supported locale as requested. Preserve source evidence and the stated Unicode counting convention.
Enter kanaText, callerKanaPatterns, callerRomajiValues using the field table and calculation rules, then run the tool.
Read romanizedWithCallerMapping, matchedPatternCount, unmatchedCodePointIndices. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
kanaText	Kana text	string	Required
callerKanaPatterns	Caller kana patterns	list of string	Required
callerRomajiValues	Caller romaji values	list of string	Required

at each position use longest matching kana pattern; otherwise preserve code point

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
romanizedWithCallerMapping	Romanized with caller mapping	string
matchedPatternCount	Matched pattern count	number
unmatchedCodePointIndices	Unmatched code point indices	list of number

json

{
  "input": {
    "kanaText": "きゃしん",
    "callerKanaPatterns": [
      "きゃ",
      "し",
      "ん"
    ],
    "callerRomajiValues": [
      "kya",
      "shi",
      "n"
    ]
  },
  "output": {
    "romanizedWithCallerMapping": "kyashin",
    "matchedPatternCount": 3,
    "unmatchedCodePointIndices": []
  }
}

Limitations and assumptions

No Hepburn/Kunrei, sokuon, assimilation or long-vowel rule is invented; include needed sequences in the mapping.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Extremely large text inputs are rejected. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use X-SAMPA to IPA Converter: X-SAMPA represents phonetic symbols in ASCII. Explicit tokens prevent ambiguity between multicharacter symbols and adjacent sounds. For a complementary task, use ARPABET to IPA Mapping Lookup: CMU ARPABET tokens encode sounds and optional vowel stress. Segment conversion should preserve stress metadata without inventing syllable boundaries.

References

Kana-Rōmaji Mapping Lookup — tool.io

Similar or alternative tools

X-SAMPA to IPA Converter
X-SAMPA represents phonetic symbols in ASCII. Explicit tokens prevent ambiguity between multicharacter symbols and adjacent sounds.
ARPABET to IPA Mapping Lookup
CMU ARPABET tokens encode sounds and optional vowel stress. Segment conversion should preserve stress metadata without inventing syllable boundaries.