A free Chromium extension
Learn Japanese on YouTube with live translations, pronunciations and word lookups on every line.
Vidoumo reads the captions YouTube already has and adds the reading over every kanji, the English underneath, and a dictionary behind every word you click.
Vidoumo
The reading,
over every kanji.
YouTube’s Japanese captions are bare kanji. Vidoumo puts the reading above each one and leaves the kana alone, so 営業 gets えいぎょう and the okurigana stay clean.
It works on automatic captions as well as uploaded ones, and the switch in the popup turns it off when you want to read unaided.
営業時間は夜12時から朝7時頃まで。
English,
under every line.
YouTube shows one caption language at a time. Vidoumo shows both: the Japanese you’re learning with the English in the same box, line by line, in step with the video.
The English comes from the video’s own subtitles when it has them, and from YouTube’s translation when it doesn’t. Only when neither works does a line go to Google. The popup switch turns it off.
人は深夜食堂って言ってるよ。
Keep the word.
Keep the moment.
Save from the dictionary card. Saved words fade to a dotted underline in later captions, so what’s new stands out. Each one keeps its sentence and a link back to the second you met it.
Export the lot as CSV when you want it somewhere else. Everything stays in your browser’s extension storage.
- 営業えいぎょうbusiness; trade; operations | sales営業時間は夜12時から朝7時頃まで。▶ 0:37 · Midnight Diner 2 (2016) - Intro Japanese Ginger Pork Set Meal For Black Dressed Woman
Export CSV · word, reading, meaning, sentence, video link
"営業",
"えいぎょう",
"business; trade; operations | sales",
"営業時間は夜12時から朝7時頃まで。",
"https://youtu.be/SMAXiL_TYkw?t=37"-
Download
Get vidoumo.zip (15 MB) and unzip it somewhere permanent. Chrome loads the extension from that folder, so keep it.
-
Extensions page
Open chrome://extensions. Edge, Brave and Arc use edge://, brave:// and arc:// instead.
-
Developer mode
Switch it on, top right.
-
Load unpacked
Choose the unzipped vidoumo folder.
-
Watch
Open a Japanese video, turn on CC and pick a Japanese track. Refresh tabs that were already open.
English from the subtitles.
To update, download the new zip, replace the folder, press reload on the extensions page, then refresh any open YouTube tabs once.
- The uploader’s English comes first. If the video has English subtitles, they now sit under the Japanese, written by a person and timed to the video, instead of a machine translation of it.
- Then YouTube’s own translation. With no English track, Vidoumo asks YouTube for its translation of the Japanese, rebuilds it into whole sentences and shows the sentence being spoken.
- Google is the last resort. Only if neither is available does a line go to Google, line by line as before. When the English comes from YouTube, nothing is sent to Google.
- English stays with its line. It arrives with the Japanese rather than a beat after, and stays up until the line ends. Hover the English to see where it came from.
Earlier
- v1.1.1 · 6 Oct 2026 · Captions that. Captions no longer type out. Vidoumo now reads the whole caption track YouTube downloads, not just what is on screen at that moment, and shows each phrase complete at its time. The box stops resizing and flickering while a line arrives. Furigana and translation are ready first. The next few lines are translated and split into words ahead of time, so they appear finished instead of filling in a moment later. Automatic captions are rebuilt into phrases. YouTube delivers them in short rows, often mid-sentence. They are joined back into sentences and paced to a normal speaking rate, so a phrase does not run ahead of the speaker, and sound notes like [音楽] stand on their own. Quiet after an update. Reloading the extension with a YouTube tab open used to throw “Extension context invalidated” errors and leave YouTube’s own captions hidden. It now steps aside cleanly. Live streams and anything it has not captured still use the earlier method of reading the screen, so nothing stops working.
- v1.0.9 · 6 Oct 2026 · First public version. Furigana, translation, dictionary cards, saved words with a link back to the moment, and CSV export.
What leaves your browser
- Subtitle lines go to Google Translate only when the video has no English subtitles and YouTube can’t translate it. Otherwise the English comes from YouTube.
- Each word you click goes to Jisho for its dictionary card.
- Saved words stay in the extension’s local storage.
Turn Translation off in the popup and subtitle text stays put.
Credits
- Dictionary entries come from Jisho.org, which is built on JMdict. © Electronic Dictionary Research and Development Group, used under its licence (CC BY-SA 4.0).
- Furigana and word splitting use kuromoji.js by Takuya Asano, a port of Atilika’s kuromoji (Apache 2.0), with the IPADIC dictionary from NAIST.