Show HN: Learn Japanese contextually while browsing

Show HN: Learn Japanese contextually while browsing(lingoku.ai)

92 points by englishcat 152 days ago | 57 comments

Hi HN,

Just wanted to share a tool i've been working on to help with my own study routine. It’s a browser extension called Lingoku.

The idea is simple: we spend hours browsing the web in English every day. This tool replaces some of the english words with Japanese vocabulary based on your japanese level (Similar to Toucan, but with a better user experience).

It’s basically an attempt to make the "i+1" method actually passive, you understand the sentence because it's mostly english, but you pick up Japanese words naturally from the context. It uses an LLM in the backend to make sure the translations fit the context (so it distinguishes between different meanings of the same word).

since it uses paid AI APIs for the words replacement, I couldn't make it 100% free (server costs are real, unfortunately). However, there is a "forever free" plan with daily credits that doesn't require a credit card. it should be enough for casual daily browsing.

I built this because I struggle with Anki burnout and wanted a way to review words without feeling like i am "studying"

It supports Chrome, Edge, and Firefox now. would love any feedback or feature requests!

https://lingoku.ai/learn-japanese

sebastiennight 152 days ago |

This is amazing. I was planning to build exactly this for movie subtitles yesterday!

I'm unsure however what you mean by

> No Ads · No Social · Zero Privacy Trace

and

> Web data is used only for real-time AI parsing, transmitted via SSL encryption, and the server never stores any original content.

Because the APIs for commercial LLMs, if you're not hosting the models yourself, definitely grab and store everything.

englishcat 151 days ago | |

Thanks for pointing this out. You're absolutely right that 'Zero Privacy Trace' was a bit too absolute.

I’ve just updated the website to be more precise: we use enterprise-grade APIs where they said data is not used for training by default, and we don't log any original content on our own servers.

We also only send the specific text snippets needed for processing to minimize exposure. I really appreciate the feedback, it helps make the project better!

socalgal2 152 days ago |

This seems relevant

https://www.youtube.com/watch?v=dcolM6W5Odc

TL;DW you have to use the words

madmod 152 days ago |

This looks really cool but I can't justify using it because of privacy concerns. Running this with a local ai and a strongly worded guarantee of no tracking/reselling of my metadata is something I would pay for.

jbstack 152 days ago | |

You could always run it in a sandboxed browser (e.g. a Firefox profile) and limit the use to just language learning (e.g. reading neutral articles online). The data you would leak wouldn't be much different than what you risk any time you browse any website.

englishcat 152 days ago | |

I can totally understand your concerns.

At the moment, Lingoku browser extension does send text to LLms for processing, we don't sell user data, but i agree that simply saying 'trust us' isn't sufficient.

Supporting local LLM is something we are actively considering, though there are still real constraints on the user experience.

laurieg 152 days ago |

Have you done any work on trying to make the opposite? Injecting English words into Japanese text to make it easier to read?

I find that students of Japanese often have enough grammar to read widely after finishing a couple of beginner textbooks, but they are completely held back by vocabulary.

englishcat 152 days ago | |

I have a deep understanding of this point, a lack of vocabulary makes reading Japanese materials very difficult.

For this scenario, we will translate the Japanese text completely into English first, then inject japanese words in to the english text, the translated text with the injected Japanese words is displayed next to the original material.

This is the main feature I've been using myself, you can try it out and see if it's the feature you want.

quamserena 152 days ago | |

I can second this, after finishing my intro Japanese classes I was able to parse the grammar of most sentences. Memorizing vocab was the hard part, so I used OCR on manga pages and then Yomitan to hover over and see word definitions (in English).

tmtvl 152 days ago | |

Isn't that what the Rikai line (10ten, Yomitan) of add-ons are for?

vunderba 152 days ago |

Nice job! There have been quite a few of these language substitution extensions over the years. (Language Immersion, Polyglot, MindTheWord, etc.)

I have a personal extension that I wrote (close to 12 years ago at this point) which does the same thing - translates random words on websites as you browse according to your linguistic level. It vastly predates LLMs though so it's all built on sentence segmentation, POS analysis for stemming, and other NLP techniques.

I've written a bunch of integrations for it so it works with websites, documents, even Kindle books.

https://mordenstar.com/projects/linguaswap

Now onto some feedback:

The site is visually a bit of a mess. The nav bar anchors but not to the top of the viewport (scroll and watch). Some of the cards are also different sizes. Some of the text isn't properly spaced (look for the colons).

englishcat 152 days ago | |

Thanks for your feedback!

LLM's makes this kind of words substitution more easier and accurate. we have also tried some methods like NLP, but effect is mediocre, but if we want use it in specific scenarios, NLP maybe more efficient.

The website's visual design definitely needs improvement. we are currently work on it.

skeledrew 152 days ago | |

I was hoping to take a look at Linguaswap, but it isn't on your GitHub. Is it available anywhere?

englishcat 152 days ago | | |

Same here, i also want to have a try.

BTW, i like the blog

shiroiuma 152 days ago |

Why is it using romaji to show the pronunciation, instead of furigana? Any serious Japanese learner will learn hiragana and katakana very early on, and these are better for reading pronunciation than romaji.

englishcat 152 days ago | |

Thanks for the feedback, actually we use furigana to show the pronunciation, we use LLM to produce the word explanation, this may be due to LLM instability, could you help tell me the word of this case on your side.

LandenLove 152 days ago |

The concept of "injecting" Japanese into text written in a different language is interesting. But I feel the presentation of word definitions are not great. Something similar to https://yomitan.wiki/ or https://jisho.org/search/kotoba would be preferred. E.g. 言葉ーことばーLanguage, word or phraseーKanji definitionsーSample sentence

englishcat 152 days ago | |

Thanks for you feedback, agreed.

The current version of word definition is somewhat rudimentary. right now we supported four languages(English, Chinese, Japanese, Korean), but we dont take much time to optimize for each language yet.

Our thought is that we will have a shared template across all the learning language, but also have abilities to customize the word definition template for language-specific needs.

atrus 152 days ago |

It's a cool idea, but the lack of a space between regular words and words wrapped in a <span> is driving my typo-radar nuts

englishcat 152 days ago | |

Really appreciate your feedback! we may have overlooked this when handling multilingual support, and we will optimize it in the next version.

FuturisticLover 152 days ago |

Is there a similar tool/extension that can show the Japanese word in romaji rather than hiragana or katakana?

Tor3 152 days ago | |

It's a very good investment to spent a week or a month (typically depending on age) to really learn hiragana. Learn hiragana and katakana in parallel. Use an app like 'Kana mind', for example, to enforce memorization.

Using romaji will, due to how the brain works, forever keep you out of learning kana properly, even when you see both at the same time. Learning kana is a small effort for a lot of gain.

marak830 152 days ago | |

Same, I love the idea - but I cannot read the hiragana/katakana (heck even: はい hai yes <- would work well).

Edit: Decided to make my own firefox addon to do it, no worry about daily limits and I can simply update a json file with more words when I feel like I'm remembering things.

terhechte 152 days ago | | |

Do you perchance have this on Github? I like the idea but would love it for another language, so would be interested in your add-on.

englishcat 152 days ago | |

I don't know a tool like this.

But this feature seems to be a fairly common requirement; we can consider add a switcher to implementing it.

61j3t 147 days ago |

I love the idea! I am working on a similar app where you learn vocabulary through context. I would like to discuss more with you, where can I reach you?

englishcat 144 days ago | |

Feel free to reach out — you can contact us via the email or Discord on our website.

skeledrew 152 days ago |

Interesting. I'd love to get something like this into things I use frequently. Primary issue for me is, though I often browse HN for example, I only do so using an app. Generally I rarely use the browser for anything beyond research and linked articles.

Tor3 152 days ago | |

After a certain age many people, and I'm definitely one of them, stop using phones for anything serious. Too small screen, unreable fonts, or alternatively zoomed-out fonts make pages unreadable anyway. So I'm basically back to using phones for, well, calls.. and a tablet or, if more than just casual, a real PC with a huge monitor if I want to actually spend some time on the net.

In short - I'm definitely now in the "browser for everything" group, I don't use apps if I can avoid it, and definitely not on phones.

skeledrew 151 days ago | | |

I'm going in the other direction. I find myself increasingly wanting to do more things with my phone, since it's always with me everywhere, and am currently somewhat actively looking into what a truly mobile-friendly UX would look like, like for example development.

englishcat 152 days ago | |

You're absolutely right, we typically spend more time our our phones for most people. we're also preparing to port this feature to mobile, possibly based on the mobile version of Firefox browser.

casey2 150 days ago |

I recommend reflection and meditation after long reading or study session to avoid burnout. Also prioritizing flashcards from books you've read can make them more meaningful.

jtonl 151 days ago |

Thank you as well for having Chinese and Korean also included!

englishcat 150 days ago | |

Hope our product helps your learning journey, enjoy! Any feedback is welcome.

jedbrooke 152 days ago |

re: > since it uses paid AI APIs for the words replacement, I couldn't make it 100% free (server costs are real, unfortunately)

is there a possibility of using local llm endpoints for this?

englishcat 152 days ago | |

we've considered using local llm, but the problem is that for a better user experience, we will add user's new vocabulary list, then inject words based on the list, it's hard to do this on local.

We will seriourly consider the point of support local llm, this will also allow more users to utilize our basic functions.

xhevahir 152 days ago |

> Just hover to get translation

Translating everything into your native language is pretty universally considered a very bad habit in language pedagogy.

rickcarlino 152 days ago | |

I hear this often but haven’t seen too many translation-free alternatives for the non-immersion tasks (eg: memorizing vocabulary for a standardized exam, daily study in a non-immersive environment). Have you seen any good monolingual techniques beyond “just get tons of exposure”?

I’ve been experimenting with monolingual vocab this month but it is too soon to say if I like it or not: https://rickcarlino.com/notes/korean-language/monolingual-vo...

Larrikin 152 days ago |

This seems interesting. I would like an Ollama version and an ability to turn off the hovering as I already have Yomichan installed.

gabmartini 152 days ago | |

Second that. An Ollama version would be great :)

jz391 152 days ago |

Interesting. The voice used for the pronunciation sound seems to be using the wrong language though (FYI using Firefox).

Tor3 152 days ago | |

I'm using the Chrome extension in Vivaldi, and I hear no sound. Yomitan and the older Yomichan work fine.

BTW, is there a way to remove the romaji? Having both hiragana and romaji together is not good.

Edit: And for some words there's _only_ romaji.. :-(

englishcat 152 days ago | |

Thanks for feedback, in some cases, we use a NLP lib to detect to language of the word since we support multiple languages, this may be due to language detection failed on some words.

rsanek 152 days ago |

some open-source options:

https://github.com/rowan-walshe/vocabify

https://github.com/GoodPraxis/oumu

bastijn 151 days ago | |

And some commercial:

https://migaku.com/

https://jointoucan.com/

socamo 152 days ago |

This is a GAME CHANGER. Is it possible to buy pro version? how can we support you?

englishcat 151 days ago | |

Thanks for your kind words, yes, but you can try the free version first, and if it's not enough, you can check the pricing plans if you like.

ekropotin 152 days ago |

Nice project!

As a struggling lifelong English learner I had an exactly same idea, but for English.

englishcat 152 days ago | |

Thanks, We now support cross-language learning between for languages (English, Japanese, Korean and Chinese), hope could help you.

OgsyedIE 152 days ago |

Do you have a roadmap for adding support for more browsers eventually?

englishcat 152 days ago | |

Thanks for your asking.

Yes, we will prioritize support for Safari, Opera, and Arc. Support for other browsers will be added as needed.

ermacaz 152 days ago |

it would be nice to see the japanese definition of the word in addition to the english definition in the hover modal

bw86 152 days ago |

I tried the pronunciation feature, which works less than awesome on my system. I am happy to share that "語彙" is pronounced "chinese letter chinese letter", while for "効果的" it is "chinese letter chinese letter chinese letter".

Is that just my Debian/Firefox system? Or is "AI slop" the reason here?

englishcat 152 days ago | |

Thanks for your feedback, appreciate it.

I tried the above words in Chrome, and got the same problem. sorry about that, our tool is far from perfect. this is a bug in the extension, we will fix it asap.

kaishin 151 days ago |

Nice concept but the design could use some love as it looks a bit on the vibe coding slop side of things.

englishcat 151 days ago | |

Fair point, the UI was partly AI-assisted, and the design is not our strongest area at the moment but something we are actively improving. Appreciate the feedback.