Experiment: German translation 🇩🇪🇨🇭🇦🇹

[caugner]

tl;dr

We're launching an experimental German version of MDN, which is targeted to those that prefer to read MDN content in German rather than English. The content is automatically translated from English using OpenAI's latest GPT-4o model, and is now available on (developer.mozilla.org). The sources can be found in the mdn/translated-content-de repository.

Note: This is an experiment, and work in progress. Translations may contain inaccuracies.

Details

MDN was available in German (de) until August 2022, when we had to remove the locale, because it was incomplete, outdated, and no longer maintained. Although we hypothesized that there was still demand for the German locale, we saw no possibility to bring it back at the time: We had evaluated automatic translations as not good enough, and considered manual translation as impossible due to the volume of MDN content, and the pace at which it is updated.

In April 2024, we re-evaluated our options, and identified LLM-based machine translation as a potential solution to revive the German locale, and to maintain it in a semi-automated way going forward.

In May 2024, we ran initial tests with LLM-based machine translation from English to German, which confirmed that the approach yields sufficient results even with a simple prompt.

In June 2024, we ran a survey (see results below) that confirmed interest in the German locale, and informed us about translation criteria, and user concerns.

In September 2024, we launched the new experimental Remember language feature, which we had identified as a blocker for the German locale in the survey. The feature effectively allows users to opt-out of the German locale.

In October 2024, we launched the public preview of the German language in an isolated test environment.

Experiment

In November 2024, we're now launching the German language as an experiment on production (without exposure to search engines). This is the first fully-translated language covering all MDN Web Docs content with over 12'500 pages, translated from the English language using OpenAI's latest gpt-4o-2024-08-06 model. (Note that most of the user interface, MDN Plus, Curriculum, and Blog are not translated.)

In December 2024, we started exposing the German translation to search engines.

To provide feedback, please rate good and bad translations using the thumbs (👍👎) in the "MDN-Feedback-Box" below the articles. If you notice any issues, please use the "Report a problem with this translation" link, write us on Discord, comment below, or send us an email (mdn-german[at]mozilla[dot]com). Please respect the Mozilla Community Participation Guidelines to ensure a healthy and constructive collaboration.

Translation process

As of December 4, 2024, the translation process includes a daily automated workflow that includes the following steps:

1. The English Markdown file is pre-processed, in particular by replacing code blocks with placeholders, converting selected macros to links, converting the YAML frontmatter to Markdown, and chunking longer documents.
2. The resulting input is passed to GPT-4o with a system prompt.
3. The resulting output is post-processed, in particular by cleaning up frontmatter, normalizing links, fixing well-known recurring syntax errors, re-inserting code blocks, and replacing link anchors.
4. The resulting German Markdown files are committed with automatic markdownlint and prettier fixes to the mdn/translated-content-de repository.

Next steps

We believe that the machine-translated German locale is helpful in its current state, even if it may contain inaccuracies.

For now, we gather user feedback, and aim to iterate on a weekly basis to address issues, and improve the quality of the translation, and the reliability of the translation process.

Our vision is for German to become a regular translated locale, and the first locale to be maintained using a combination of machine translation, and community reviews.

Appendix: Survey

In June 2024, we ran a survey on MDN for 5 days that was shown to all users whose browser preference indicated German as the preferred language.

Goal

The goal of the survey was to test our hypothesis that there is demand for the German language, understand our users' language proficiency and preference, translation priorities, and concerns.

Participation

The survey was seen by over 60'000 users, and over 1'900 users completed it (3%).

Language proficiency and preference

We asked about language proficiency:

• 90% of participants indicated German as their native language.
• Of these, 33% rated their English as basic or advanced, not fluent.

(Note: German language preference correlated inversely with English language proficiency.)

We asked what language they would use if MDN was available in German:

• 62% participants indicated a preference for English (54% would use mostly English, 8% more English),
• 35% participants indicated a preference for German (24% mostly German, 8% more German), and
• 3% participants indicated no preference.

Translation priorities

We asked what would be important in a German version of MDN:

1. Technical correctness (89% Very important)
2. Consistency of technical terms (73% Very important)
3. Up-to-date ness (68% Very important)
4. Completeness (56% Very important)
5. Comprehensibility (50% Very important)
6. Linguistic correctness (31% Very important)
7. User interface in German (14% Very important)
8. Graphics in German (8.3% Very important)
9. Code examples in German (7.5% Very important)

Concerns

We asked an open-ended question, and 13% of participants answered it, providing context for their responses, or sharing concerns.

Among users who indicated no preference or a preference for German there were no significant patterns, apart from praise and gratitude (n = 18; thank you!).

Users who indicated a preference for English …

• … explained their preference with programming languages and technical terms being in English (n = 59), and having better experiences with English documentation, being more complete and up-to-date (n = 44).
• … rejected automatic or AI translations, criticizing them as inaccurate and incomprehensible (n = 34), and sharing negative experiences with machine-translated technical documentation (n = 19).
• … emphasized that they don't want to be redirected to the German language (n = 21), even if their browser indicates German as the preferred language, and mentioned the need to permanently switch to the English version (n = 10).
• … suggested having translations reviewed by the community to improve their quality (n = 12).
• … acknowledged that some users, especially beginners, could benefit from a German translation to better understand technical concepts (n = 11).

Limitations

The main limitation of the survey is its appearance in the context of non-German content, so potential users who only speak German may be under-represented. On the other hand, users who are interested in the German locale may be more likely to respond to the survey, and therefore over-represented.

[yatil]

Love how this page in German encourages people to "make use of diarrhea" ("Ausnutzen des Durchfalls"). "AI" translations are really innovative stuff. /s

Hire translators.

[AliveDevil]

Microsoft can’t get their automatic translations up to quality, who own OpenAI, how’s MDN going to get this right? You’ll be constantly fighting with the model.

Piece if Evidence A: „DLL Surrogate“ is not „DLL-Ersatzzeichen“.

[caugner]

Thank you for trying out the experimental German translation, and for taking the time to provide this feedback. 🙌

Love how this page in German encourages people to "make use of diarrhea" ("Ausnutzen des Durchfalls").

First of all, great catch! 🙂

Looking into the translation history of this page, 3 out of 4 translations used the English term "fall-through", while only the most recent one replaced it with the German words "Durchfall" and "Durchfallen".

While this translation is not necessarily incorrect, it highlights a trade-off: leaving a term untranslated (e.g., "fall-through") vs. using a German equivalent that, while technically accurate, might feel unconventional or humorous to some readers. I have re-translated the page with our latest prompt, which now uses "fall-through" again: mdn/translated-content-de@b58ce94

@yatil Could you confirm whether "fall-through" should remain untranslated? If a German translation is preferred, do you have a suggestion for an alternative that might work better? Based on your input, we can update our translation glossary to ensure consistent handling of this term moving forward.

how’s MDN going to get this right? You’ll be constantly fighting with the model.

@AliveDevil MDN is committed to transparency in its approach to machine translation, and we encourage the Community to participate in refining the German translation. We believe that collaboration and feedback from both beginners and experienced developers will significantly improve translation quality over time. To support this, we’re actively seeking input through multiple channels, such as the "MDN-Feedback-Box" at the bottom of every translated page, discussions like this one, and the #german channel on Discord.

Please continue to share any terminology issues you spot, along with your suggestions for improvements. 🙏 Your feedback is invaluable to us.

PS: We kindly ask everyone to follow the Mozilla Community Participation Guidelines to ensure a constructive and respectful collaboration. Let’s stay direct, but also positive and solution-oriented. 😊

[yatil]

I will not help support machine-translated resources, so I cannot reply to your question, even if I knew the answer.

[kaiserkiwi]

While this translation is not necessarily incorrect

It is. "Ausnutzen des Durchfalls" is not the correct translation. "Taking advantage of fall-through" is translated with "Taking advantage of diarrhea" in this post.

"Ausnutzen des Durchfallens" would be technically correct. Even if it's a completely weird way to write.

You want to know what shouldn't be translated automatically from your AI? Everything. Hire translators or keep it in English. Please this does more harm for everyone involved that it helps anyone.

[caugner]

The re-translation of the switch page is now live, see: Ausnutzen des Fall-through-Verhaltens.

[tomayac]

Could you confirm whether "fall-through" should remain untranslated?

Yes, this should remain as is. "Ausnutzen des Fall-through"-Verhaltens" is how I would translate it.

[caugner]

Thank you. I double-checked, and this is the only page that uses this term, and the current translation now consistently uses the term "Fall-through".

[philo1989]

Pls just dont..... It's teribble. Make it an Option for people who need it but not the default pls....

Another part to consider... Do you really want to particapte in the llm hype and contribute an not insignificant energy need on a pet project like a german translation... . They need to build new power plants for this bs and you Support that?

[caugner]

@philo1989 Thank you for your feedback.

I invite you to try out the experimental Remember language feature that allows you to set your preferred language, and ensures that you will always be redirected there if the current page exists in that language.

[jampy]

Why not adhere to the standard Accept-Language instead? Being german my mother language, I also have english in that list, as I understand both languages fine. So my browser tells you literally "the client prefers german and if that is not available, english".

The automatic translations pratically always contain nonsense and are counterproductive, especially on tech topics. It's annoying to turn off this stuff on increasingly many sites (Microsoft, Google, ...).

If I would need a translation I would ask the browser to translate the page with the inbuilt translator.

[teetotum]

I second what @jampy posted: I configured the user settings of my browser to use 1. German 2. English and this is not meant as a request to feed me machine translations. Yes, I see that you provide an opt-out, but you got it wrong, it shouldn't be opt-out, it should be opt-in if anything.
Even your own survey results show that the overwhelming majority of users would still prefer the english version even if a german version was available:

We asked what language they would use if MDN was available in German:

• 62% participants indicated a preference for English (54% would use mostly English, 8% more English),

To activate it for all users by default is not only annoying, it is patronizing.

[davibu]

@philo1989 Thank you for your feedback.

I invite you to try out the experimental Remember language feature that allows you to set your preferred language, and ensures that you will always be redirected there if the current page exists in that language.

Why is an experimental feature forced onto users instead of opt-in?
Even if this experimental feature is opt-out, why is there no direct way of switching back to English inside the banner?
Why is there no possibility to complain about the translation as the default inside the feedback section?

And even your survey doesn't seem really conclusive. I really don't get on what basis this feature is considered useful.

I hate these localization, as they make my life harder to simply read some documentation, just because I'm a non-native English speaker.
And I know from quite a few peers I'm not the only one.

English is a mandatory subject in German school system, everyone needs to acquire English skills. So if your target audience for MDN is German children under 14 than this feature may be useful, but elsewise it is not.

It makes life harder as these translations are always not quite right. There may be figures that not fit the text, even variables that may be cross referenced inside the documentation text. And sometimes translated terminology is simply harder to understand. If you want to find more information it's alot harder as these translations are never consistent and even if they would be consistent there would be alot more English content out there.

In the "best case" it would lead to more content tailored to a specific language, but this would result in less helpful results on Google or any other search engine, as every language would use their own terminology or phrasing.
The result is splitting the programming community by language instead of being inclusive.

Cross referencing English and translated documentation is really hard even if you are quite familiar with English and German terminology. Cross referencing is alot harder than consistently using English for docs.
Even the Google result suggest that the result is English to then find these awful translation when you click on it. If I would want a German version I would search for a German version.

Instead of this translation effort you could consider finding passages that are hard to understand for non-native speakers and improve these sections or try to use some language processing to find words or phrases that are uncommon and as such less known by non-native speakers. You may even try LLMs to find sections that might be hard to understand or even establish a workflow that require easy readability before something is added to the docs.

But this AI-translation are not a good solution and even docs on Google or Microsoft that had these kind of translation for quite some time still fail to deliver quality results.
If you still want to pursue these translations than at least make them opt-in or find a better solution that fixes these concerns in a systemic way. Wikipedia for example made the language selection more prominent, which is quite nice. You could make the translated version a separate site like Wikipedia, that can be indexed by Google, so if someone searches for German information that is on MDN they could find it.
But forcing (hidden opt-out) German people into a solution that they don't want is not nice.

[jampy]

Also, I'm having a hard time figuring out how to switch to the original version. There is a link to this issue here, but no "switch to original".

[caugner]

@jampy You can switch to the original version by selecting "English (US)" in the language switcher on the top right:

You can enable "Remember language" to always be redirected to that language, even if clicking on a /de/ link (e.g. when using a search engine).

[jampy]

@caugner thanks, but it's not really easy to find in the mobile version (it's hidden in one of three menus). Since there is already a banner for the translation experiment visible, a direct command would be useful.

[kleinph]

I had also a hard time finding the language option on mobile. Please don't do this by default.

At least put an "Switch to original" prominently in the info box.

[Vanilagy]

Thank you for this effort. I personally will not use this myself, but this will certainly be immensely helpful to a lot of German-speaking people.

Please don't be let down by the criticism, I think machine translation is a revolutionary tool that enables the world to be understood by more people, and with LLMs, it has come so far that it can reliably translate large structured documents like those found on the MDN docs. Obviously, mistakes will still happen but that's what the feedback function is for.

[wparad]

Please don't make assumptions on what would be good for other people if you are not part of that group.

[GHXX]

I am part of the german speaking group, and i can say i find it incredibly annoying. I have been hit with autotranslated content also on the microsoft c# docs page for instance, and on reddit, and it is incredibly frustrating. basically before i can interact with the content i have to turn it off, because i absolutely want reliable information. Information that has a traceable source. Translations are never as accurate as the original, and this really matters in many cases of programming (think about security, reliability, data integrity, etc. - this is stuff i really do not want to jeopardise).

I have seen that there appears to be a way of having the site remember my choice, though i really think this translation feature does not bring any real benefit whatsoever.
Like, English is my second language, and German is my primary one, yet i still have to switch it to English so that the information has a clear source. So I would argue that it does in fact not help anyone that wants to be certain - and if you start reading documentation you usually do want to be certain, otherwise you could also just give it a shot and see what happens.

Please do not participate in this trend, MDN.

[Vanilagy]

@wparad I too am a native German speaker and English is only my second language - and I too prefer text in its original version and switch all documentation I read to English. But surely, for people who are not yet well-versed in the English language, 95% accurate translations should be helpful and lower the barrier of entry for them - even if the translations feel a little awkward and stiff at times. The German option is also completely additional to the rest of MDN and there is no obligation to use it.

What I do understand can be annoying, and I would be annoyed by this myself, is if websites would constantly autoswitch to German based on my location or something and ignore my preference. I have all my locales set to English, so this doesn't really happen for me anymore, but I can't speak on how MDN behaves regarding this matter.

[kleinph]

@Vanilagy but these are developer docs not user facing help sites, and most German speaking developers I know prefer the original English version. That's why I think here it should be the other way round: displaying a banner that say's that the docs are also available in (auto translated) German.

[Vanilagy]

@kleinph Yeah of course, I think that makes sense. This feature shouldn't be an annoyance to the German devs who always go for the English docs.

I just found that there's this toggle here:

It seems like this was explicitly added to address the issue that people want a fixed language, but their search engine might return localized results first.

[schlagmichdoch]

Some external links seem to be encapsulated with parenthesis in the auto translated version which completely breaks them:

See https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API/Using_Service_Workers#demo

On that page the link behind simple service worker running live is changed:
Original: https://bncb2v.csb.app/
Auto-Translated German: (https://bncb2v.csb.app/)

This is a relative path that links to https://developer.mozilla.org/de/docs/Web/API/Service_Worker_API/(https://bncb2v.csb.app/).

This should not happen with software that only translates strings.

Please switch this off.

[caugner]

Thanks for the report, this is now fixed via mdn/translated-content-de@815643e.

PS: I checked, and this was the only occurrence of this issue. If this happens again, we will consider refining the translation automation.

[renehsz]

I appreciate the effort to make MDN more accessible. Unfortunately, as a developer with German as my native language, I see this change as a significant regression.

Your own survey results show that the majority prefers English, which makes sense given the high English proficiency among German-speaking developers. But even for the other group, I'm sure that they're not particularly pleased with the low quality of the articles on MDN now. Most of the translated content isn't technically incorrect (save for "Durchfall" which was absolutely incorrect, there's no denying it). But LLMs tend to create such a jungle of words that doesn't just sound weird, but is significantly more difficult to comprehend! This is especially true for technical jargon, which users effectively have to translate back to English to understand.

The current implementation feels like a solution looking for a problem. This is especially true for users who have both de and en in their Accept-Language header. This clearly states: I am proficient in both languages. Given the choice, show me the original language. DO NOT auto-translate, unless the content is neither in de nor in en!

(In case you're wondering, setting en as my first and de as my second preference is great until I run into the exact opposite problem: Sites that are in German originally end up showing me bad English translations. So this problem isn't unique to MDN. But up until recently, it wasn't a problem on MDN at all, so this is a regression!)

So, please, Mozilla, stop forcing your US-centric world view upon us. Many users strongly dislike or have a hard time reading technical documentation in any language other than English because it is the standard language in software development! I wouldn't even want a human-translated version, but shoving machine-translated content in my face is quite frankly insulting.

I commend your effort to improve accessibility for one group, but only as long as it doesn't negatively impact the other in a big way. (The other group being larger by the way, according to your own survey).

Please consider implementing one or both of the following solutions:

1. Allow users to opt in to machine translations instead of having to opt out.
2. Only serve machine translations if the original language of the content (en) is not in the Accept-Language header. (Users could still override the default and turn translations on manually.)

Option 2) would serve both groups better by respecting user preferences.
And no, having an opt-out feature is not an acceptable excuse not to have sensible defaults.

Thank you for considering this feedback.

[teetotum]

This! So much This! Thank you for articulating what I strongly feel myself but lack the patience and emotional self-command to type up; coherently, eloquent, clear, while staying polite.
The way this ill feature was pushed upon us is patronizing and insulting. It deigns to do something on my behalf I never asked for, nor need, nor want, and is even getting in my way to boot. And I reckon that this is the case for the majority of users.

[chk1]

The translations read unnatural and not "fluid", quite... machine-like, they are not good. I use several devices and have to find the language toggle every time. Please make disabling translations a one-click.

On mobile there are two menus, the "hamburger" and "three dots". Both are unlabelled, it's just frustrating to use this way.