Short answer: there is no one permanent "Joker trailer URL." The official trailers for Joker (2019) live on Warner Bros. Pictures' own YouTube channel and on the studio's film page, and those are the two places I would send anyone. Everything else you find through a search is either a re-upload, a reaction cut, or an edit with someone's watermark over it.

What counts as an official trailer link

Warner Bros. controls the marketing for the film, so the uploads on the studio's verified channel are the source. A re-uploaded copy can look identical frame for frame, but it can disappear without warning, get muted for music rights, or sit on a channel that also posts unrelated junk. If you need to cite a trailer or embed it somewhere that matters, use the studio upload.

The trailers worth knowing

The teaser (April 2019)

This is the one most people mean when they say "the Joker trailer." It runs about two and a half minutes, opens on Arthur Fleck at work, and closes on the talk show set. It is the clip that drove most of the early conversation about the film.

The final trailer (August 2019)

Longer, more plot, more of the Murray Franklin material. If you are looking for the version with the full stair-dance sequence, this is it.

Folie à Deux (2024)

The sequel has its own teaser and full trailer, also handled by Warner Bros. Those are separate uploads, so a link to a 2019 trailer is not going to show you the sequel.

How I check a link before passing it on

• Look at the channel name and the verification badge, not the video title. Titles are easy to fake.
• Check the upload date against the film's release window. A "first trailer" posted years later is a re-upload.
• Scan the description for the studio's standard copyright block.
• Watch the first few seconds for a third-party logo or channel intro. Official uploads do not open with someone's branding.

If you need a link that will not rot

1. Grab the URL from the studio channel while the video is live.
2. Note the video ID separately, since the ID survives most page changes.
3. Keep the film title and release year with the link so a reader can find a replacement if the original goes down.

One more thing. Search results for this phrase are crowded with aggregator pages that repost the embed and wrap it in ads. The trailer plays, but the page is not the source. If accuracy matters, go to the studio.