Rolko
Web app + browser extension · Learn Japanese from real content

Turn real Japanese into lessons you remember

Explore words while you watch, browse, or read. Keep the ones you want to remember.

Free includes lookup, reading, and limited translation. Saving new words starts with Starter.

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YouTubeGB
毎日少しずつ勉強すると、覚えやすくなります。★
0:00 / 0:15
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The web app works on mobile. The browser extension is for desktop.

See how learning Japanese works

This example uses Japanese content with English meanings.

Reading workspace

毎日使える日本語

Tap or hover a word for its pronunciation and meaning. Mark it as learned or learning.

Word Coverage

Learned: 25%Learning: 25%New: 50%
先生
毎日少しずつ勉強すると、覚えやすくなります。

Review with spaced repetition

The right words return at the right time, in short daily sessions that stick.

Review with spaced repetition

Vocab Review

毎日
毎日少しずつ勉強すると、覚えやすくなります。

Your vocabulary at a glance

Find every word you save, filter by status, and see its pronunciation, meaning, and examples.

4 words
覚える
おぼえる
to remember; to learnStatuslearningNext reviewIn 1 week
勉強する
べんきょうする
to studyStatuslearningNext reviewIn 1 week
少しずつ
すこしずつ
little by littleStatuslearningNext reviewIn 1 week
毎日
まいにち
every dayStatuslearnedNext reviewIn 1 week

Keep track of your progress

See how many words you know, your review streak, daily activity, and each word’s mastery.

rolko.xyz/app/stats
Saved vocab
10,200
7,500 learned
2,700 learning
Learned
7,500
+12 today
+48 this week
Learning
2,700
−2 back to learning today
−8 back this week
Review queue
0
Recommended today: 0
Streak
47 days
Best 61
78 active days
Vocabulary progress
7,500 learned · 2,700 learning · 10,200 total
Learned 73.5%Learning 26.5%
Movement
today
+12 learned
-2 back to learning
this week
+48 learned
-8 back to learning
This month
+120 learned
-18 back to learning
This year
+7500 learned
+10,200 saved
Words moved to learned (last 90 days)
Review activity
Daily reviews · Accuracy trend
Daily reviews
1,227 vocab
30 days
Jun 1
58 total
Jun 2
69 total
Jun 3
44 total
Jun 4
78 total
Accuracy trend
Right-answer % per day, 30 days · rest days skipped
92% avg
Avg
92%
High
93%
Low
91%
Due now
Words due for review right now.
Nothing is due right now.
Weak
Still learning — review interval under 7 days.
少しずつ
little by little
Oct 29
勉強する
to study
Oct 30
覚える
to remember; to learn
Oct 31
Mastered
Graduated to learned status.
毎日
every day
Oct 28

Make real progress

Learn from real content while watching, browsing, and reading

Discover real Japanese words. Save them, review them, remember them.

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