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Hepburn Romanization: How to Read Japanese in the Latin Alphabet
There is a moment every learner of Japanese goes through. You see the word 東京 written on a sign, and it is beautiful, and you have no idea what it sounds like. The characters carry meaning and sound at the same time, but only if you already know them. Before you have studied kana and kanji, they are elegant drawings that tell you nothing about pronunciation.
Romanization serves as the bridge. It writes the sounds of Japanese in the Latin alphabet, the same twenty-six letters you are reading right now, so that someone who has never studied the language can sound out a word and get close to how a Japanese speaker would say it. And the system that does this job, the one your textbook uses, the one on Japanese road signs and train stations and passports, the one the entire internet defaults to, is Hepburn romanization.
The system is not new. An American missionary named James Curtis Hepburn popularized it in 1867, in the first Japanese-English dictionary, though the system itself was developed by the Rōmaji-kai (Romanization Club), a society of Japanese and foreign scholars of which Hepburn was a member. What is new is that in December 2025, the Japanese government made Hepburn the official national romanization standard, the first revision of the national rules in about seventy years. The system the world was already using is now the system Japan officially recommends.
Hepburn romanization is a system for transcribing Japanese sounds into the Latin alphabet, designed so that an English speaker reading the result will pronounce the word close to how a Japanese speaker would. That is the entire design principle, and every property of the system flows from it.
The principle comes with a trade-off. Hepburn is phonetic for English speakers, not systematic for kana. The syllable し is written "shi" and not "si," because "shi" is closer to how し sounds to an English reader. This is the core decision that defines Hepburn and drives every difference from its competitors. A system that maps kana to romanization in a regular, one-to-one way writes し as "si," which is cleaner as a rule but misleading as a pronunciation guide. Hepburn chose pronunciation over consistency.
There are three variants worth knowing. Traditional Hepburn is the original system from the 1867 dictionary, which romanized some sounds in ways that have since been refined. Modified Hepburn, also called Revised Hepburn, is the modern standard: it regularized a few edge cases and is the version used in textbooks, passports, and most dictionaries. The third variation concerns macron usage, particularly whether the long "i" gets a macron (sensei vs sensē), which is a matter of style rather than a substantive difference.
James Curtis Hepburn was an American Presbyterian missionary and physician who arrived in Japan in 1859, one of the first Westerners to settle in Yokohama after the country opened to foreign trade. He was a doctor by training, but his lasting contribution was lexicographic. Over eight years, with the help of Japanese assistants, he compiled the first Japanese-English dictionary, published in 1867. The romanization system in that dictionary was a practical tool: it let English speakers look up Japanese words they could not yet read, and it let them pronounce what they found.
The dictionary went through multiple editions. The third edition, published in 1886, adopted the system refined by the Rōmaji-kai, the Romanization Society, a group of Japanese and foreign scholars who had been working on standardizing romanization. This is the version that became the standard and is essentially what we now call Modified Hepburn.
Hepburn was not alone. His chief assistant was Kishida Ginkō, a Japanese scholar who contributed substantially to the dictionary and the romanization system. The collaboration is worth noting because it means Hepburn romanization, despite bearing an American name, was a joint Japanese-American project from the start.
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