Yomitan (Yomichan): The Hover-Dictionary Workflow
Yomitan is a free browser extension that turns any Japanese web page into a hover dictionary. Hold a key, point at a word, and its reading and meaning appear in a popup without leaving the page.12 For a learner reading native digital text, it removes the biggest drag on momentum: stopping to type an unknown word into a separate dictionary.
Overview
Yomitan is the maintained successor to Yomichan, the popular pop-up dictionary whose original author discontinued it.1 It installs as a browser extension, reads the text under your cursor, and shows definitions in an in-page popup. The setup below takes a blank install to a working hover dictionary with the right starter dictionaries, audio, and fonts.
What a hover dictionary does for reading
A hover dictionary (ホバー辞書) sits as a lookup layer under whatever you are reading. You hold a modifier key, hover over a word, and Yomitan returns the reading and meaning in a popup. Then you keep reading.12 It is the low-friction middle ground in the larger question of when to look up a word vs. infer it: the cost of a lookup drops to a keypress.
The default scan trigger is Shift-hover: hold the modifier key, described in the project documentation as "Hold the modifier key (default: Shift)," over the text you want to look up.2 The modifier is customizable in settings.
The popup also handles deconjugation. Hover over an inflected verb or adjective, and Yomitan looks it up by its dictionary form, or lemma, so you do not have to know that base form yourself.2
A fresh install returns nothing on hover. Yomitan shows a "Dictionary Required" state, flagged by an orange exclamation mark on the toolbar icon, until at least one dictionary is loaded.2 Installing the extension and importing dictionaries are two separate steps.
As a quick mental model of one lookup, picture hovering over the dictionary-form verb 食べる while reading: hold Shift, point at it, and the reading and meaning appear in the popup. That single word is illustrative only, not a quoted example.
Yomitan and the end of Yomichan (February 2023)
Yomichan, built by foosoft, was discontinued by its owner on 26 February 2023; the README of the maintained fork states it was "sunset by its owner on Feb 26, 2023."1 The project did not disappear so much as change hands.
Yomitan is the community-maintained successor fork, developed under the yomidevs organization on GitHub, whose README says plainly that "Yomitan is the successor to Yomichan."1 It carries the original project forward and ships a migration guide for users moving across.1
This is why older guides written for "Yomichan" still largely apply. The workflow is the same, the names of a few settings have shifted, and the install target is now Yomitan.1
If a tutorial tells you to install "Yomichan," follow its setup logic but install Yomitan instead. The 26 February 2023 discontinuation is a fixed historical event, so this guidance does not expire.1
Installing the extension
Yomitan installs through the official add-on store for your browser. The path differs slightly between Chromium browsers and Firefox, but both end at the same first-run check.
The whole process has three stages. Seeing them in order helps avoid the "why are my lookups empty" confusion.
Chromium browsers (Chrome, Edge, Brave)
On Chrome, install from the Chrome Web Store. The documentation lists "Install from Chrome Web Store" as the stable channel, with a separate beta build available.2 On Edge, install from Edge Add-ons.2
Chromium-based browsers such as Brave install Yomitan from the Chrome Web Store, the same stable channel Chrome uses. So the Chrome path applies to them as well.2 After installing, pin the Yomitan icon to the toolbar so settings stay one click away.
One Chromium-specific toggle, "Allow access to file URLs," is needed later for reading local files. It is covered in the Good to know section below.3
Firefox
On Firefox, install from Mozilla Add-ons (AMO). The documentation lists "Install from Mozilla Add-ons" as the stable channel.2
Beta and testing builds for Firefox are not published on AMO. They are side-loaded manually from the GitHub releases page, which most learners will never need.2
First-run check: hover a word
Open settings by clicking the Yomitan icon in the toolbar, then the cog labeled "Settings."2 This is also where you control the scan modifier and every later option.
The default scan trigger is Shift-hover, and it is customizable in settings.2 Test it on any Japanese web page before importing anything.
Expect lookups to come back empty at this stage. Until a dictionary is imported, Yomitan stays in its "Dictionary Required" state. The next step fixes that.2
Importing dictionaries
Dictionaries give Yomitan its answers. A small starter set covers words, names, and individual kanji. One improved build replaces the plain word dictionary for English readers.
The starter set: JMdict, JMnedict, KANJIDIC
Three dictionaries form the foundation, each covering a different kind of lookup.
| Dictionary | Covers | What it is |
|---|---|---|
| JMdict | Words | The core Japanese-multilingual word dictionary, with Japanese as the pivot language.4 |
| JMnedict | Proper names | Japanese place-names, surnames, given names, company names, and titles of works.56 |
| KANJIDIC | Single kanji | Readings, meanings, and other information about individual kanji characters.6 |
JMdict is the workhorse. Its project aims at "the compilation of a multilingual lexical database with Japanese as the pivot language," which in practice means Japanese-to-English for most learners.4 JMnedict, derived from ENAMDICT, holds "Japanese proper names; place-names, surnames, given names, company names, names of artistic and literary works, product names, etc."5 KANJIDIC is "an English dictionary listing readings, meanings, and other info about kanji characters," covering the 6,355 kanji in the JIS X 0208 standard.67
All three are produced and owned by the EDRDG (Electronic Dictionary Research and Development Group). The group was founded at Monash University in 2000 from J. W. Breen's dictionary files, and the dictionaries are released under a Creative Commons Attribution-ShareAlike Licence (V4.0).7 For Yomitan, they are distributed as .zip files from the yomidevs build repository. Import them as-is, without unzipping them.8
Jitendex: the recommended JMdict build
Jitendex is "a free, offline, and openly licensed Japanese-to-English dictionary" built on the EDRDG's JMdict database. It adds example sentences, usage notes, etymology, and cross-references.9 It is the same underlying data as JMdict, with better formatting on top.
The Yomitan documentation recommends it over plain JMdict for English users, calling it "an improved version of JMdict for Yomitan" and advising "we recommend installing the more modern Jitendex for English users."6
Jitendex is released under the same Creative Commons Attribution-ShareAlike Licence (V4.0). Its word data comes from the EDRDG, and the bundled example sentences come from Tatoeba under a CC BY 2.0 FR licence.10 New versions are published on a recurring schedule, so it stays current without manual effort.9
Importing and ordering dictionaries
The fastest path is the recommended-dictionaries shortcut. In settings, open the language dropdown and choose "Get recommended dictionaries…". Add custom dictionaries through "Configure installed and enabled dictionaries" then "Import."2
Whichever route you take, import each dictionary as its distributed .zip file. Do not unzip it first.8 Yomitan reads the archive directly.
Once several dictionaries are loaded, you can enable, disable, and reorder them so the build you trust most appears first in the popup.26 For instance, dragging Jitendex to the top puts its entry at the head of every lookup.
Audio, pitch accent, and fonts
With dictionaries in place, three finishing touches make each lookup more complete: pronunciation audio, pitch-accent display, and clean Japanese rendering.
Adding audio sources
Yomitan can play pronunciation audio inside the popup. For Japanese, its default audio sources are "JapanesePod101" and "Jisho.org," checked in that order.3
Configure audio at "Settings > Audio > Configure audio playback sources." The interface supports text-to-speech, custom URLs, and preset sources that you can reorder.3
Forvo, described in the documentation as "currently the largest online pronunciation database," can be added through a custom URL.3 A local audio server is the heavier-duty option, with broader coverage. It is best set up alongside an SRS workflow, covered in Yomitan + Anki: One-Click Card Creation, rather than here.3
The default JapanesePod101 source occasionally gives a wrong reading or lacks a word entirely. Treat popup audio as a strong hint, and cross-check anything that sounds off against a pitch-accent dictionary or a second source.3
Showing pitch accent
Yomitan displays pitch accent the same way it displays everything else: through an imported dictionary. Once a pitch-accent dictionary is loaded, the accent pattern appears in the popup alongside the entry.6
Pitch accent shapes how a word sounds and, in some pairs, what it means. That is why seeing the pattern at lookup time is worth the extra dictionary. The dedicated treatment of pitch accent lives in Japanese Pitch Accent: A Complete Beginner's Guide.
Fonts and rendering
If the popup or page shows tofu (empty boxes) or garbled glyphs, the cause is almost always a missing or misconfigured Japanese font. The project's tech-support guidance addresses this.11 Confirming that your operating system has Japanese font support installed resolves most cases.
Yomitan's own appearance and font-size settings adjust how the popup renders. This helps when the text is legible but too small or cramped.11
Good to know
"Allow access to file URLs" for local files
In Chromium browsers, Yomitan will not work on local files until "Allow access to file URLs" is enabled for the extension.3 This includes local .html pages used by in-browser readers like ttu-reader: The In-Browser E-Reader for Japanese and the OCR output of Mokuro: OCR for Japanese Manga. It is the single most common reason a working install seems to "stop working" the moment a learner opens an offline reader.
Set it on the browser's extensions page. You can also use "Settings > Security > Configure Yomitan Permissions" and then check "Allow access to file URLs" on Chrome and Edge.3 On Firefox, the equivalent option is "Access your data for all websites."3
Keep the scan key out of your way
The scan modifier is configurable. Shift is the default, with Ctrl, Alt, or no key as alternatives.2 The choice matters more than it looks.
A no-key setting opens the popup whenever the cursor passes over Japanese text, which constantly interrupts reading. A deliberate modifier key keeps the popup out of the way until you actually want a lookup, so a held key is the conventional choice.2
Yomitan is the lookup layer, not the whole workflow
Yomitan is best understood as the foundation other reading tools sit on top of, rather than a complete workflow by itself. It provides the on-hover lookup. The reader, the OCR layer, the subtitle layer, and the spaced-repetition hand-off all build on a working Yomitan install.12
Getting this base layer right is the prerequisite for everything else in a digital reading workflow. The sibling guides in this subcategory each assume a Yomitan install that already works.
See also
- Yomitan + Anki: One-Click Card Creation
- Kindle for Japanese Learners
- How Reading Builds Japanese Ability
- Sentence Mining: Building Your Own Japanese Anki Deck From What You Read
- Japanese Pitch Accent: A Complete Beginner's Guide