Explore
Discover videos in your target language, matched to your level.
How It Works
The Explore page shows recommended videos for your language pair. Each video is sourced from YouTube and selected for language learning. By default the feed includes music and entertainment content; use the Exclude music & entertainment toggle below the pills if you'd rather see only other kinds of videos.
Videos are sorted by popularity and filtered by difficulty when you select a level. The recommendation engine learns from your watch history, so videos you've already watched won't appear again.
Level Filter
The pills at the top let you filter by proficiency level. The labels adapt to your target language:
| L2 | Pills show |
|---|---|
| Chinese | HSK 1 → HSK 7-9 |
| Japanese | JLPT Pre-N5 → N1 |
| Korean | TOPIK Pre-1 → 6 |
| English | IELTS 1 → 9 |
| Others | CEFR Pre-A1 → C2 |
Click a pill to filter videos at that level. Click All to see videos at every level. Click Kids to see recommended kids videos across all levels — the Kids pill and the level pills are mutually exclusive, so picking one clears the other. Kids videos are only shown when the Kids pill is selected; the default feed excludes them. The filter remembers your choice as you browse, and resets to your saved proficiency level when you return.
Video Cards
Each card shows a color-coded level badge in the top-left corner. See How Difficulty Is Calculated for how these levels are determined.
Click any card to open the video player. When you return to Explore, your place in the list is preserved exactly where you left it.
Channel Actions
Each video card has a … menu in the top-right corner with two options:
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Subscribe — Videos from this channel will appear first in your recommendations. About 25% of each page is reserved for subscribed channels, so you'll always see their newest content near the top. This is useful for channels you want to follow regularly — news outlets, educational creators, or your favorite vloggers.
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Not interested — Videos from this channel will be hidden from your recommendations entirely. This is useful for channels that consistently show up but aren't a good fit — maybe the content is too advanced, too easy, or just not relevant to your learning goals.
Your channel preferences are saved per language, so subscribing to a Japanese news channel won't affect your Korean recommendations. You can manage all your subscriptions and hidden channels from your profile.
How Difficulty Is Calculated
Every video is assigned a difficulty score based on the frequency of words in its subtitles. The system uses per-language Zipf frequency lists — large tables that rank how common each word is in real-world text. A word like "the" has a high frequency (common), while "sesquipedalian" has a low frequency (rare).
The scores are bucketed into 7 levels using exponential thresholds: the top 1/127 most frequent words are level 1, the next 2/127 are level 2, the next 4/127 are level 3, and so on — doubling each step. Level 7 covers the rarest 64/127 of words.
Because word frequency distributions differ between languages, the thresholds are language-specific. A difficulty score of 0.008 in Japanese maps to JLPT N1 (level 6), while the same score in Korean maps to TOPIK 3 (level 4). The frontend fetches these thresholds once from the backend and uses them to label every video card.
Your channel preferences are saved per language, so subscribing to a Japanese news channel won't affect your Korean recommendations. You can manage all your subscriptions and hidden channels from your profile.
Tips
- Set your proficiency level on your profile page so Explore starts with the right filter
- Switch levels to find easier or harder content — switching back is instant
- Toggle Exclude music & entertainment to keep music and entertainment videos out of the feed
- Your watch history is private and only used to avoid showing the same video twice
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