If you cut one version for every platform, cut it to 3 minutes, vertical, 1080 by 1920. That length works everywhere: it sits inside Instagram’s recommendation window, it matches the length available to every TikTok account, and it hits YouTube Shorts’ ceiling exactly. That convergence is our analysis from the figures below, not a statement any platform made. The table gives the comparison, and the sections after it show where the platforms’ own pages agree and where they disagree.
The comparison, at a glance
The table below is our own synthesis of the pages cited in this guide. Read it as a comparison, not as any platform’s table.
| Spec | Instagram Reels | TikTok | YouTube Shorts |
|---|---|---|---|
| Longest upload (in-app) | 20 minutes, in one clip or several clips adding up to that length (Instagram Help Center, “Record a reel on Instagram”) | In-app: 3 minutes on every account, some accounts 5 or 10; the posting API accepts up to 10 minutes (spec roundup citing TikTok’s developer docs) | 3 minutes, square or vertical, uploaded on or after 15 October 2024 (YouTube Help Center, “Understand three-minute YouTube Shorts”) |
| New-audience reach | Reels over 3 minutes are not recommended to new audiences (Instagram Help Center) | For You feed recommendation; ineligible content is harder to find in search, and content created by account holders under 16 is ineligible (TikTok For You feed Eligibility Standards) | Videos up to 3 minutes are categorised as Shorts and can earn in Shorts revenue sharing from the Shorts Feed (YouTube Help Center) |
| Aspect ratio | 1.91:1 to 9:16 (Instagram Help Center, “Reel size and aspect ratios”) | 9:16 recommended; 1:1 and 16:9 also accepted (CapCutGuide guide, quoting TikTok’s developer docs) | Square or vertical (YouTube Help Center) |
| Minimum quality | 720 pixels resolution, 30 frames per second (Instagram Help Center) | API route: 360 pixels per side, 23 to 60 frames per second (guide quoting TikTok’s developer docs) | No minimum stated on the pages opened for this guide |
| Other limits | API route: 3 seconds to 15 minutes, up to 300 MB (Meta’s IG User media reference, as quoted by Eksis) | API route: up to 4 GB; MP4, WebM or MOV; H.264, H.265, VP8 or VP9 (guide quoting TikTok’s developer docs) | Title max 100 characters (YouTube Help Center, “Upload YouTube Shorts”) |
Instagram: 20 minutes to upload, 3 minutes to reach strangers
Instagram’s Help Center article on recording a reel says you can record and edit videos up to 20 minutes with Reels, in one clip or several clips adding up to that length. The same article carries the sentence that matters more for reach: reels over 3 minutes will not be recommended to new audiences. In practice, a 12-minute Reel can exist, but Instagram’s own wording is that it will not be recommended to new audiences.
The size rules sit in a second Help Center article: a reel’s aspect ratio must fall between 1.91:1 and 9:16, with a minimum resolution of 720 pixels and a minimum frame rate of 30 frames per second. Vertical 9:16 at 1080 by 1920 satisfies all of it, which is one more reason the 3-minute vertical master is the safe export. That 1080 by 1920 figure is our export recommendation from those minima, not a figure Instagram states.
Instagram even disagrees with itself here, and the disagreement is worth reporting rather than smoothing over. The body of the recording article says 20 minutes, while the Help Center’s own search summary for the same article says 3 minutes. Until Instagram fixes one of the two, treat 3 minutes as the reach boundary and 20 minutes as the upload ceiling, and never quote 3 minutes as the upload ceiling.
TikTok: 3 minutes everywhere, higher caps on some accounts
TikTok’s developer documentation, as quoted by independent spec guides, sets the baseline every account shares: all creators can post 3-minute videos, while some accounts have access to 5-minute or 10-minute videos. Each account has its own maximum, so a long file posted through a scheduling tool can need trimming first. The posting API itself accepts up to 10 minutes, up to 4 GB, in MP4, WebM or MOV, at 23 to 60 frames per second and 360 to 4096 pixels per side, with 9:16 recommended at 1080 by 1920 (CapCutGuide, quoting TikTok’s developer docs). One spec roundup reports TikTok Studio accepts up to 30 minutes, so the ceiling depends on the route as well as the account; 10 minutes is the API maximum, not a confirmed universal in-app ceiling.
The surface that matters is the For You feed, TikTok’s personalised recommendation feed. Its eligibility page says content that is ineligible for the feed may also be made harder to find in search, though it can still be discovered through search tools or by following an account. Content created by account holders under 16 is ineligible, and the page’s consolidated list counts 15 ineligibility categories. Repetition of dieting, extreme fitness, sexual suggestiveness, sadness and overgeneralised mental-health themes gets interrupted rather than banned outright. Our TikTok algorithm guide covers that eligibility system in full.
One number to leave out of your planning: 60 minutes. Hour-long uploads were a limited test in select markets, confirmed to TechCrunch in May 2024, with no wide rollout. Three minutes works on every account, 10 minutes is the API ceiling, and 60 minutes is not a standard limit.
YouTube Shorts: 3 minutes, and two rules that are mid-change
Shorts run up to 3 minutes, and the categorisation rule has dates attached. Standard channels: videos uploaded on or after 15 October 2024 with a square or vertical aspect ratio up to 3 minutes are categorised as Shorts and can be monetised in the Shorts revenue-sharing model from the Shorts Feed. For Official Artist Channels the same categorisation rule applies to uploads on or after 8 December 2025. Older uploads stay long-form. Shorts can be uploaded through the YouTube app and YouTube Studio, and titles run to a maximum of 100 characters.
Two rules are currently stated differently on YouTube’s own pages, so this guide states both instead of picking one. First, music: the three-minute Shorts page says most songs can be used for up to 90 seconds in a three-minute Short, with some tracks limited to 60 or 30 seconds, while the upload-flow page notes 15-second clips for audio picked from the library in the mobile upload flow. Those are different workflows, not one ceiling stated two ways. Second, copyright claims: the older US English three-minute page wording says a Short over one minute with an active Content ID claim will be blocked globally, while other official YouTube guidance says new Shorts between one and three minutes will no longer be blocked automatically from 24 September 2026. The change is about automatic blocking; it does not rule out every form of blocking. Until the pages agree, treat claimed audio past the one-minute mark as a risk, and keep the Shorts surface discussion to the comparison table rather than re-teaching surfaces covered in our YouTube views guide.
What to export
Export one master: 3 minutes or shorter, vertical 9:16, 1080 by 1920, 30 frames per second. It clears Instagram’s recommendation boundary, the length available to every TikTok account, and Shorts’ ceiling in one file. Go longer only with a reason: a Reel over 3 minutes for an audience that already follows you, or a TikTok up to your account’s own cap after checking it first, since a tool will trim what your account cannot take. For the scheduler route, our scheduling-tools comparison carries the full API matrix; this guide stays on the in-app specs.
Can I post the same 3-minute video on all three platforms?
Yes, as a length and shape it fits all three: inside Instagram’s recommendation window, at the length available to every TikTok account, and at Shorts’ ceiling. Format, captions and music still need a per-platform pass, since music and claim rules differ.
Why does Instagram say 20 minutes in one place and 3 minutes in another?
The Help Center article body says record and edit up to 20 minutes, with a note that reels over 3 minutes are not recommended to new audiences. The Help Center’s own search summary for the same article says 3 minutes. The two cannot both be the ceiling, so this guide treats 20 minutes as the upload ceiling and 3 minutes as the reach boundary.
Is TikTok 60 minutes now?
No. Hour-long uploads were a limited test in select markets, confirmed in May 2024, with no wide rollout. Three minutes works on every account and 10 minutes is the API ceiling.
Do Shorts over 1 minute get blocked for copyright claims?
It depends which YouTube page you read. The older US English page wording says a Short over one minute with an active Content ID claim will be blocked globally. Other official YouTube guidance says new Shorts between one and three minutes will no longer be blocked automatically from 24 September 2026, and that change covers automatic blocking, not every form of blocking. Until the pages agree, treat claimed audio past one minute as a risk.
What aspect ratio is safe everywhere?
Vertical 9:16. Instagram accepts 1.91:1 to 9:16, TikTok recommends 9:16, and Shorts require square or vertical. A 1080 by 1920 vertical file satisfies all three.
Does a longer Reel reach fewer new people?
According to Instagram’s Help Center, yes: reels over 3 minutes will not be recommended to new audiences. Length past 3 minutes sits outside the new-audience recommendation window.
