Nicovideo Downloader

Overview

Half the fun of Niconico is watching comments fly across the screen, but the site's slow servers and Premium-only quality tiers make the experience frustrating. Nicovideo Downloader saves your favorite videos as clean MP4 files and exports the scrolling comments as subtitle files you can load in VLC or MPV. Same magic, zero buffering.

Whether you are archiving Vocaloid classics, saving MAD videos before they get taken down, or collecting Japanese learning material, this tool handles it all. Batch download entire mylist playlists, keep the original Japanese titles and video IDs in your filenames, and get Premium-tier quality when your account supports it.

Everything runs locally in your browser. Your Niconico activity stays completely private.

Why It Exists

• Watch Niconico content with scrolling comments offline, preserving the full experience
• Access premium-quality streams offline without Niconico's player buffering issues
• Archive Vocaloid music videos, MAD videos, and game content before they are deleted
• Save Japanese learning materials and cultural content for study without internet access

Key Features

• Download Niconico videos in the highest quality available to your account tier
• Export scrolling comments (danmaku) as ASS subtitle files for offline viewing
• Support for Niconico Premium quality tiers including high-bitrate streams
• Batch download from mylist playlists, user upload pages, and search results
• Preserve Japanese titles, tags, video IDs (sm/nm numbers), and upload metadata
• Handle Niconico's session authentication for member-only and premium content
• Automatic audio and video stream merging for Niconico's DASH delivery format
• Queue downloads with per-item progress tracking and automatic retry on failure
• Output as MP4 with optional MKV container for advanced subtitle embedding
• Works on Chrome, Edge, Firefox, Brave, and Opera on Windows, macOS, and Linux

How It Works

• Install and log in: Add Nicovideo Downloader to your browser and sign into your Niconico account for access to your authorized content.
• Open a video page: Navigate to any Niconico video, mylist playlist, or uploader page and the extension detects available streams and comments.
• Download with comments: Choose your quality tier, optionally enable danmaku comment export, and start the download or queue multiple videos.
• Watch with scrolling comments: Load the MP4 and ASS subtitle file together in VLC or MPV to experience Niconico's signature scrolling comments offline.

Reviews

• Comment overlay export preserves the Niconico experience perfectly (5/5): The comment export is what makes this special. I archive Vocaloid music videos from Niconico and the scrolling comments are half the experience. The ASS subtitle export reproduces them perfectly in MPV. - Yuki Watanabe
• Invaluable for Japanese language study from Niconico (4.9/5): I study Japanese and Niconico is a goldmine for learning material. This downloader saves videos with the original Japanese titles and sm IDs so I can find them again later. The batch mylist download is incredibly useful. - Chris Davenport
• Premium quality downloads with proper DASH handling (4.8/5): I have a Niconico Premium account and this actually downloads at the premium quality tier. Other tools I tried were limited to economy quality. The DASH stream merging handles Niconico's format without any desyncs. - Sakura Fujimoto

Platform Support

Browsers

• Chrome
• Edge
• Firefox
• Brave
• Opera

Operating Systems

• Windows
• macOS
• Linux

Supported Content

• Niconico videos with comment overlay export as ASS subtitles
• Premium quality streams for Niconico Premium subscribers
• Mylist playlists and user upload page batch downloads
• Japanese titles and sm/nm video ID metadata preservation

Not Supported

• Active Niconico Live broadcasts still streaming
• Premium quality without a Niconico Premium subscription
• Content you are not authorized to view on Niconico
• Safari and mobile browsers

Privacy and Permissions

Supported regions: Worldwide.

Limitations:

• Niconico account login required to access most content.
• Premium quality streams require an active Niconico Premium subscription.
• Economy-hour quality restrictions apply to free accounts during peak times.
• Live broadcast timeshifts must still be available for viewing to be downloadable.
• DASH stream merging requires the browser tab to remain open during processing.
• Safari and mobile browsers are not supported.

Permissions:

• downloads: Saves downloaded MP4 video files and ASS comment subtitle files to your local downloads folder.
• activeTab: Detects the Niconico video player on the current page to show download options only on nicovideo.jp pages.
• storage: Stores quality preferences, download queue state, and completed download history locally in the browser.
• notifications: Notifies you when downloads or batch mylist queues finish processing.