AIStacker
LanguageNew

Overview

Kana ↔ Romaji Converter

Convert between hiragana, katakana, and Hepburn romaji. Handles sokuon (っ), long vowels (ー), small ya/yu/yo combinations, and ん before vowels.

What isHow to useExampleCommon use casesFrequently asked questions

Category hub

Language

Problems

5

FAQ

3

Quick links

Browse hub
#hiragana-to-romaji#katakana-to-hiragana#hepburn-romanization#japanese-input#romaji-converter

Kana ↔ Romaji Converter

Hepburn romanization for Japanese kana, plus hiragana ↔ katakana conversion. Handles sokuon (っ), long vowels (ー), small ya/yu/yo combinations, and ん before vowels.

Output appears here

Hepburn romanization rules applied:

  • し → shi, ち → chi, つ → tsu, ふ → fu, じ → ji
  • っ doubles the next consonant: かっこう → kakkou
  • ん before あ/い/う/え/お/や/ゆ/よ becomes n' for disambiguation
  • ー (katakana long vowel) repeats the preceding vowel: コーヒー → koohii
  • Romaji → kana uses longest-match Hepburn input rules

What you can solve

How do I correctly Hepburn-romanize a Japanese name for a passport?

Japanese passport applications expect modified Hepburn. Type the name in hiragana or katakana, select Kana → Romaji, and copy the output. Verify long vowels: お段 + う is typically romanized as 'o' alone in passports (とうきょう → Tokyo, not Toukyou), so adjust the output by hand for ō → o if your jurisdiction requires the simplified form.

I imported a Japanese Anki deck but I need romaji on the front — can I batch convert?

Export the deck to CSV, paste the kana column here in Kana → Romaji mode, copy the result, and paste back as a new column. Re-import. Sokuon and long vowels are handled, so romaji renders cleanly without manual fixes.

I have a hiragana list but I need it in katakana for a vocabulary worksheet — fastest way?

Paste the hiragana list into Hiragana → Katakana mode. The conversion is a direct codepoint shift (+0x60), so it preserves line breaks and punctuation. Copy the result and paste into your worksheet template.

How do I convert long katakana loanwords like コンピューター to readable romaji?

Paste the katakana in Kana → Romaji mode. Long vowel marks ー are expanded to repeated vowels (コンピューター → konpyuutaa, スマートフォン → sumaatofon). The output is the readable Hepburn form used in most English-Japanese tech glossaries.

Why does my romaji output have apostrophes in words like han'i?

The apostrophe disambiguates ん followed by a vowel from a regular な-行 syllable. Without it, hani could mean はに or はんい. The tool inserts the apostrophe wherever ん precedes あ・い・う・え・お・や・ゆ・よ. Remove it manually for stylistic preference; the kana → romaji direction is unambiguous either way.

Typical workflow

Japanese Text Counter - Ninja Character CounterKana ↔ Romaji ConverterKanji Density AnalyzerJapanese Character Limit Checker

Guides for this workflow

Supporting guides that connect this tool to the broader category workflow.

Open category hub
Language guide

Japanese Writing & Content Creation Hub: Counters, Readability, and Romanization

A workflow hub for Japanese writers, teachers, and content creators — character counters, kanji density, JLPT level checking, romanization, manuscript paper, and reading-time estimation in one map.

Language guide

Check Japanese Character Limits Before Submitting Essays and Entry Sheets

A practical workflow for checking Japanese character limits before submission so a draft does not fail because it is visibly short, quietly over, or counted under the wrong rule.

Language guide

Estimate Japanese Reading Time for Scripts, Lessons, and Study Content

A workflow for estimating Japanese silent reading and read-aloud time so scripts, lessons, and study materials fit their real timing constraints.

Language guide

When to Use Genkouyoushi Counts Instead of Raw Character Count

A practical guide to when Japanese writing should be thought of in manuscript-paper sheets instead of raw characters, especially for assignments, essays, and draft planning.

What is

What is Kana ↔ Romaji Converter?

Romanizing Japanese kana looks trivial until you hit the actual edge cases: っ doubles the next consonant, ー stretches the preceding vowel only in katakana, ん before a vowel should be written n' to avoid ambiguity (han'i, not hani), and ち/つ/ふ/し follow Hepburn (chi/tsu/fu/shi), not the Nihon-shiki ti/tu/hu/si that many auto-converters output. This tool handles all of those cases by default.

It also covers the everyday hiragana ↔ katakana swap that every learner and translator needs, and a reasonable romaji-to-kana input mode that uses longest-match Hepburn rules. Use it for name romanization, JLPT vocabulary lists, transliterating loanwords, or building input that other Japanese tools expect.

How to use

How to use Kana ↔ Romaji Converter

1. Pick a direction: kana → romaji, romaji → hiragana, romaji → katakana, hiragana ↔ katakana.

2. Paste or type the source text. Output regenerates instantly.

3. Copy or use the result downstream (Anki, name cards, transliteration sheets).

Example

Example

Hiragana → Romaji:
とうきょう → toukyou
おおさか → oosaka
にっぽん → nippon

Katakana → Romaji:
コーヒー → koohii
ラーメン → raamen

Romaji → Hiragana:
konnichiwa → こんにちわ
tokyou → とうきょう

Common use cases

Common use cases

1. Generate Hepburn-romanized names for passports, business cards, or visa forms.

2. Convert imported Anki kana decks to romaji for early learners.

3. Romanize loanword katakana (コンピューター → konpyuutaa) for technical documentation.

4. Swap between hiragana and katakana when preparing test items for JLPT writing practice.

Frequently asked questions

Frequently asked questions

Why does ん before a vowel become n' instead of just n?v
Because han'i (はんい, range) and hani (はに, Hani — a name) would otherwise look identical. The apostrophe is the standard Hepburn disambiguation. The tool inserts it whenever ん is followed by あ, い, う, え, お, や, ゆ, or よ.
How does the long vowel ー get romanized?v
It repeats the preceding vowel (コーヒー → koohii, ラーメン → raamen). Some publishers prefer macrons (kōhī) — if you need that form, run the output through a find/replace afterwards: oo → ō, uu → ū, ee → ē, ii → ī, aa → ā.
Does the romaji-to-kana mode follow standard input method conventions?v
Yes — it uses longest-match Hepburn input rules with double-consonant gemination (kk → っk, tt → っt). Type tokyou for とうきょう, kk for っk. The ん handling treats nn and n' both as ん.