Japan Has a Translation Style Standard. It Stops Before Your Copy.
Your Japanese copy came back accurate. The terminology is right, the claims survived legal, a native speaker checked it. It still reads as a translation.
The reasonable next question is whether there is a standard for this — something the work could have been held to. There is one, it is public, and it was revised in July 2026. It is worth reading what it governs rather than trusting the title, because the scope is narrower than the name suggests, and the standard is unusually direct about where it stops.
What the standard actually standardizes
The Japan Translation Federation publishes a style guide for translating into Japanese. It is written in Japanese, and the passages quoted here and below are our own translations, not official English versions.
Its stated purpose is specific:
The purpose of the JTF Style Guide is to serve as a guideline for unifying Japanese orthography in translation into Japanese.
Then it separates two decisions that a brief usually treats as one:
Because Japanese uses many kinds of characters, translating into Japanese means that, at the same time as considering “how to translate it,” one must decide “how to write it.”
It is not the purpose of the JTF Style Guide to explain the “translation technique” needed to translate appropriately, or the “composition technique” needed to write practical prose clearly.
Two layers are named there, and the document claims one of them. How a sentence is transcribed is in scope. How it is built is out.
That is not a gap the guide left by accident. Its own reference list points to a separate book, published by a different body, for the composition side. The division is between documents, not inside one.
The twelve headline rules are consistent with this. Unify the register. Use Japanese commas and periods. Prefer the standard kanji list. Follow the standard okurigana forms. Keep the long vowel at the end of loanwords. Full-width for kana and kanji, half-width for digits. These are decisions about characters on a page.
The rules for what the source leaves behind
The part that bears directly on commissioning English-to-Japanese work is a run of rules in the punctuation chapter. They exist for one situation: the source text contains a mark, and the question is what happens to it.
Seven separate rules turn on that situation, and they answer it the same way: the Japanese does not follow the source. On exclamation marks:
In practical translation, exclamation marks are not used often in body text. Even where the source text uses an exclamation mark, use a period in the Japanese wherever possible.
The guide then works the example in both languages:
[Source] Just plug it in, and coffee is ready in three minutes!
[Translation] プラグを差し込めば、3分でコーヒーができます。
Question marks are handled the same way, with their own worked pair. Colons and semicolons are not used in Japanese, and specifically not used where the source has them — though the colon keeps one Japanese use of its own, and the semicolon keeps none. Curly brackets and single quotation marks are permitted only where the source genuinely has to be reproduced. Angle brackets are converted rather than carried across.
Read them together and one instruction repeats: a mark in the source is not a reason for a mark in the translation. The guide comes back to it across seven rules in two chapters.
Not one of the seven says it without a hedge. Six of them carry a stated exception — headings and advertising copy for the exclamation and question marks, a separate Japanese use for the colon, formulas for the angle bracket, faithful reproduction for the two bracket pairs. The seventh, the semicolon, carries no exception at all. It still opens with as a rule.
On the question it returns to most often, inside the layer it does govern, the document does not issue a single unconditional prohibition.
These are the places where the source language is visibly still present. They are also where the guide prints an English sentence and its Japanese rendering one above the other, labelled source and translation.
One rule was removed for being too intricate
The fourth edition keeps a revision history, itemized by page. One entry records a removal, and it is the line worth reading:
3.2.9 Dash (—): Description of the dash removed. The rules are fine-grained, and it was becoming too involved.
The dash did not stop being a problem. English uses it constantly and Japanese handles it differently, so every translator meets it. The rule was removed because writing it down was getting complicated, not because the case was settled.
The document works this way throughout, and its own maintenance record is where that becomes visible. A norm specifies what can be specified while remaining usable. Where a case has too many branches, the standard withdraws and the decision goes back to a person — and this one is candid enough to log the retreat.
Notice that nothing in that explanation is about Japanese. It is about what a written rule can carry: rules stop where the next one would need more exceptions than it is worth stating. The subject here happens to be Japanese orthography, and the reason the guide stops where it does has nothing to do with the language.
The fields it was written for
The fourth edition, published in July 2026, added a chapter that did not exist before: a survey of how the guide is actually applied across translation fields. It names the fields it covers, following the ISO 17100 categories:
IT and localization · Industry and science and technology (other than IT) · Medicine and pharmaceuticals · Patents and intellectual property · Finance, economics and law
It also records which category was dropped, and the reason:
“Other” is not covered. In the “Other” fields, uniform rules have not become established, and the character of the work is heavily case-by-case and client-by-client.
The guide describes its own origins in the same terms, and says how it expects to be used outside them:
The JTF Style Guide was edited on the basis of knowledge and experience concerning scientific and technical documents, and IT and localization in particular. Meanwhile, each translation field sometimes operates its own rules and conventions. In that case, of course, please give priority to the circumstances of the field, and refer to the JTF Style Guide for the parts where no rule or custom exists.
Read that as the instruction it is. The guide expects each field to have its own conventions, and offers itself for the leftovers. It is written to sit underneath something.
Look at the list and decide where a brand campaign sits. The guide is not making a claim about advertising; it is stating which fields it studied. But the answer to why there may be no settled standard for the thing a brand is commissioning is written down, by the body that would have written that standard: in the territory it set aside, uniform rules have not become established.
The two statements meet in an awkward place. The document expects to sit beneath a field’s own conventions — and the category it set aside is the one where, by its own account, those conventions have not become established.
Where it does apply, it defers
The same new chapter is explicit about who has the final say on notation:
Whatever the field and whatever the project, it goes without saying that the client’s wishes take priority on matters of notation. What is collected here is a tendency, no more.
And it reports what actually happens in practice:
The survey found that “conforming to a client-supplied style guide” is common. In IT and localization, a client’s pre-existing style guide is frequently specified.
The document that looks like the external standard describes itself as the fallback. In the ordinary case, the governing document is the one the brand supplied — which will have been written in the home market, for writers in the home market. Why a guideline like that stops working on arrival is a separate subject, and we have written about it.
There is one more deferral worth noticing. The exclamation mark rule has an exception, and so does the question mark rule, and both name the same category:
However, in cases such as headings, advertising-related text, and sentences that call the reader’s attention emphatically, use an exclamation mark where its use is judged appropriate.
Even inside the layer the standard does govern, the case closest to brand copy is returned as a judgment call. Not prohibited, not specified — judged.
What is left for someone to decide
Put the pieces in order and the position is clear enough.
There is a standard, and it covers orthography. It says in its opening pages that translation technique and composition are not its purpose. It was built from technical and IT documents. It names five fields and excludes the residual category because rules there have not settled. It hands notation to the client’s own guide when one exists. And where its rules would touch advertising, it marks the case as a judgment rather than a rule.
So a Japanese text can be fully conformant and the question the brand actually cares about will not have been asked anywhere in the process. Not because someone skipped it. Because it is not a question the conformance step contains.
That leaves it as somebody’s decision — and this is the part worth being deliberate about, because a decision nobody has been assigned still gets made. It gets made by whoever is closest to the sentence at the moment it has to ship: a translator working to a supplied glossary, a local marketer who was sent the file for a quick look, a project manager reconciling two rounds of comments.
Each of those people is doing what they were asked. None of them was asked to own how the copy reads, and the question of who holds the parts nobody’s contract covers is its own problem.
The useful move before commissioning is smaller than it sounds. Ask what your Japanese copy is being checked against, and read that document rather than trusting its title. If the answer is a style guide, look at what it says its purpose is. The one described here states it under the first heading of its introduction.
Source: JTF日本語標準スタイルガイド（翻訳用）第4.0版 / JTF Japanese Standard Style Guide (for Translation), 4th edition. Japan Translation Federation, Translation Quality Committee. Published 25 July 2026. https://www.jtf.jp/pdf/jtf_style_guide.pdf — by Japan Translation Federation (CC BY 4.0). All quotations above are our own translations from the Japanese original.