What Is Danmaku? How to Download Bilibili Bullet Comments and Find Any Video's Highlight

If you've ever opened a video on Bilibili (哔哩哔哩, B站), you've seen them: comments flying across the screen, right on top of the video. Those are danmaku (弹幕, "bullet comments"), and they're one of the most interesting datasets on the Chinese internet.

In this post:

1. What danmaku actually is, and why it's useful data
2. How to download Bilibili bullet comments without a login (no code, or Python)
3. How to find any video's highlight moment from danmaku density

👉 Tool used: Bilibili Danmaku Scraper on Apify · Source on GitHub

What is danmaku (弹幕)?

Danmaku literally means "bullet curtain". On Bilibili, each danmaku is a short comment that viewers post at a specific second of the video. Everyone who watches later sees it fly across the screen at that same moment.

Some you'll see everywhere:

Unlike normal comments, every danmaku has a timestamp. That makes it unusually good data:

• Highlight detection: where danmaku spike, something happened.
• Second-by-second audience reaction: for trailers, ads, product launches or game reveals.
• Sentiment over time: when do viewers love it, and when do they complain?
• Clip finding: creators use spikes to decide which moments to cut into shorts.

How to download Bilibili bullet comments (no login)

Bilibili has no public API for danmaku, and there's a catch: logged out, Bilibili serves danmaku from two different endpoints. One gives a sample across the video's whole lifetime, the other the most recent few thousand. They barely overlap, so most simple scripts miss a lot.

The Bilibili Danmaku Scraper merges both. On a 34-minute video that gave 5,416 danmaku rows without logging in.

Option 1: No code

1. Open the Bilibili Danmaku Scraper and click Try for free.
2. Paste video links, or give it search keywords, UP主 (creator) IDs or the popular/ranking feed.
3. Click Start, then Export to Excel, CSV or JSON.

Example input: the danmaku of the top 10 search results for a keyword, plus a free summary per video:

{ "searchQueries": ["原神"], "maxVideosPerSource": 10, "videoSummary": true } 

Each row is one bullet comment:

Pricing: $1 per 1,000 danmaku, no subscription. The per-video summary rows are free.

Option 2: Python

git clone https://github.com/Dunkmap/Bilibili-Danmaku-Scraper cd Bilibili-Danmaku-Scraper pip install -e . bili danmaku BV1xx411c7mD -o danmaku.csv 

Find a video's highlight from danmaku

The quick way: the free summary row

With videoSummary: true, every video gets one extra free row before its danmaku, with:

• count: how many danmaku
• density: a 20-slice timeline of how busy each part of the video is
• peak_time: the busiest moment, which is usually the highlight
• top_phrases: the most repeated phrases
• samples: a handful of distinct texts

So you can find the highlight of 100 videos without paying for a single danmaku row. Just read peak_time.

The DIY way: pandas

If you exported the full danmaku as CSV:

import pandas as pd df = pd.read_csv("danmaku.csv") df = df[df["content"].notna()] # keep danmaku rows only  # danmaku per 30-second window df["window"] = (df["time"] // 30) * 30 per_window = df.groupby("window").size() peak = per_window.idxmax() print(f"Highlight around {int(peak // 60)}:{int(peak % 60):02d}") # what people were saying at the peak at_peak = df[df["window"] == peak]["content"] print(at_peak.value_counts().head(10)) per_window.plot(kind="bar", figsize=(12, 4), title="Danmaku per 30 s") 

At the peak you'll typically see a burst of 前方高能, 名场面 or 哈哈哈.

Useful extras

• Keyword filter (keywords): keep only danmaku containing certain words, for example a brand or product name. Filtering happens before charging, so you only pay for matches.
• Sentiment analysis: label each danmaku positive, neutral or negative.
• Delta mode: for scheduled monitoring, return only danmaku that are new since the last run.

Need comments, video stats or UP主 profiles too? Use the full Bilibili Scraper.

FAQ

What does danmaku mean? 弹幕 (danmaku) means "bullet curtain": comments that fly across a video at the moment they were posted.

What is the difference between danmaku and comments? Comments sit below the video. Danmaku are tied to a playback second and appear on top of the video.

Can I download Bilibili danmaku without an account? Yes. No login or cookie is needed.

Can I export danmaku to Excel? Yes. On Apify, click Export → Excel. Locally, use -o danmaku.csv.

How do I hide danmaku on Bilibili? Click the 弹 toggle under the video player. (You don't have to hide it to scrape it. 😉)

Have you used danmaku data for something interesting, like trailers, esports or music videos? Tell me in the comments! And if you try the Bilibili Danmaku Scraper, I'd love your feedback.