TL;DR YouTube states Shorts can be up to 3 minutes long, and that square/vertical videos up to three minutes uploaded after specific dates are categorised as Shorts. Build your workflow around that reality: format, packaging, and the right “link surface”.
1 What counts as a Short now (official)
YouTube Help states:
YouTube Shorts creation tools support short-form videos up to 3 minutes long.
Videos uploaded after October 15, 2024 with a square or vertical aspect ratio up to three minutes are categorised as Shorts.
Videos uploaded after December 8, 2025 with a square or vertical aspect ratio up to three minutes are categorised as Shorts (with a different monetisation treatment for some rights-holder scenarios).
In the rights-holder context, YouTube also notes: Shorts longer than one minute that have an active Content ID claim will be blocked.
2 The 3-minute Shorts publishing checklist
2.1 Before you edit
Decide if this is a Shorts-first story (one self-contained arc) or a Shorts-to-longform bridge (tease → related video).
Lock the CTA surface (end screen, related video link, channel profile link, etc.).
2.2 While you edit (Instavar defaults)
Keep the message legible on mobile: large type, strong contrast, minimal clutter.
Design the first frame as a “thumbnail substitute” for Shorts (because Shorts don’t accept custom thumbnails the same way long-form does).
Export multiple hook variants if you plan to test.
2.3 Upload + packaging
Upload via the YouTube app or YouTube Studio (YouTube explicitly supports up-to-3-minute Shorts uploads there).
If you’re driving to long-form, add a Related video link for Shorts (this is a native surface built for that flow).
3 Rights/music gotcha: avoid silent failures
If you’re using music or third-party audio, treat rights as a first-class constraint. YouTube explicitly calls out that Shorts longer than one minute with an active Content ID claim will be blocked in the rights-holder guidance.
4 Official references
YouTube Help — Get started creating YouTube Shorts (includes “up to 3 minutes”): https://support.google.com/youtube/answer/10059070?hl=en