Castmate
How to cast Niconico videos to your TV
Tested October 27, 2026 with Castmate for Chrome.
- Open the Niconico video in Chrome and start playing it.
- Click the Castmate icon in the toolbar. The video shows up with its title, length and quality.
- Press Cast and pick your TV. This site needs the Castmate relay (a small Mac app, coming soon): the video goes through your computer, so keep it on and awake while it plays.
What we found
- Casting works through the relay. Niconico only serves its video to its own pages, so the TV can't open the stream directly. In our test it played with the Castmate relay running on the computer. The relay is a small Mac app that isn't released yet; until it is, Niconico videos can't be cast with Castmate.
- Saving isn't possible: Niconico encrypts its streams, and Castmate doesn't get around that.
Test details
| Tested | October 27, 2026, Castmate 1.0.5, Chrome on macOS |
|---|---|
| Stream | HLS stream (.m3u8) |
| Best quality found | 384p H.264 |
| TV | onn. 4K Plus (Google TV, Chromecast built in): played through the relay on the computer |
If it stops working, press Didn't work? Report it under the video in Castmate and we'll look at Niconico again.
Only save videos you have the right to keep. Niconico is a trademark of its owner; Castmate isn't affiliated with or endorsed by Niconico. All guides ยท Support