Watch any Niconico (Nico Nico Douga) video with English subtitles overlaid on the player, or download a finished SRT/VTT/ASS file. No Japanese account required. 50 free credits at signup — no card required.
Pick the workflow that matches how you watch. Both use the same translation engine and the same 30+ target languages.
Install the VinnerVi browser extension, open any Niconico video, click the extension icon, and pick your target language. Translated subtitles appear on the Niconico player, synced to playback. Since Niconico rarely carries non-Japanese caption tracks, the extension transcribes the audio with AI first at 3 credits per minute, then translates into your target language.
Open vinnervi.com/subtitles, paste the Niconico link (nicovideo.jp), pick a target language and a subtitle format (SRT, VTT, ASS, or TXT), and hit Generate. The finished subtitle file arrives in your Jobs tab and your inbox — useful for archiving fan-translated content, language study, or building an English-language Niconico personal library.
Niconico (Nico Nico Douga, nicovideo.jp) is the oldest and most distinctive Japanese video platform — home to vocaloid music, MikuMikuDance animations, retro gaming archives, Touhou content, indie anime, niche otaku culture, and a long tail of Japanese creators who never crossed over to YouTube. The platform's signature danmaku overlay (user-posted comments flying across the screen) and member-driven culture make it one of the richest cultural archives on the Japanese-language web — and one of the least accessible to non-Japanese speakers. Fan-translation communities have historically been the only path in, and they cover a tiny fraction of the catalog.
VinnerVi opens that catalog to everyone. The browser extension overlays English (or any of 30+ other target languages) subtitles directly on the Niconico player, so you can watch a vocaloid producer's behind-the-scenes commentary, a retro gaming long-play, or a Touhou doujin video with subtitles synced to playback. The URL workflow gives you a downloadable subtitle file — useful for fan-translators bootstrapping a starting transcript, archivists preserving Niconico content with translations attached, or Japanese learners working from material no traditional textbook covers.
Because Niconico rarely carries built-in caption tracks (even Japanese subtitles are uncommon), most videos run in audio-transcription mode at 3 credits per minute. The AI transcription handles natural Japanese conversational speech well, including gaming commentary and vocaloid song lyrics; quality is highest on clean studio audio. No Japanese phone number, no Niconico account, no premium subscription required — public videos work for everyone. VinnerVi translates the audio into subtitle text; Niconico's user-posted danmaku comments are a separate overlay and are not translated.