YouTube publishes five numbers for Shorts, and a file size limit is not one of them. Maximum length, maximum resolution, aspect ratio, title length and how many files you can queue at once are each stated outright in YouTube's help centre. The megabyte cap you have seen quoted elsewhere is not — because YouTube has never published one for Shorts.
That gap is where most "Shorts specs" pages go wrong: they fill every row of a tidy table, and the rows YouTube leaves blank get filled with numbers borrowed from somewhere else. Below, every filled cell is a quote and every blank one is blank because YouTube does not say.
The specs, at a glance
| Spec | What YouTube states | Source page |
|---|---|---|
| Maximum length | "Up to 3 minutes." | Upload YouTube Shorts |
| Aspect ratio | "With a square or vertical aspect ratio." | Upload YouTube Shorts |
| Maximum resolution | "You can upload Short videos with a maximum resolution of 1080p." | Get started creating YouTube Shorts |
| Title length | "max 100 characters" | Get started creating YouTube Shorts |
| Files per upload session | "You can choose up to 15 short videos at a time" | Upload YouTube Shorts |
| Where you can upload from | "through the YouTube app and YouTube Studio" | Understand three-minute YouTube Shorts |
| File size limit | Not published for Shorts | — |
| Minimum length | Not published | — |
| Minimum resolution | Not published | — |
Sources: YouTube's help centre articles on uploading Shorts, getting started with Shorts and three-minute Shorts.
Notice what is not in that table: 9:16. YouTube's wording is "square or vertical" on both the upload page and the classification page. It never narrows that to a ratio. A 4:5 clip is vertical. A 1:1 clip is square. Both qualify by YouTube's own phrasing.
The two conditions that turn a video into a Short
This is the mechanism worth understanding, because it is automatic and it applies whether or not you intended it. YouTube classifies by aspect ratio and duration together, not by which button you uploaded through.
The three-minute Shorts page states it for standard channels: "Any videos uploaded on or after this date with a square or vertical aspect ratio up to three minutes in length will be categorized as Shorts on YouTube." The date in that sentence is October 15, 2024 for standard YouTube channels. Official Artist Channels have their own cutoff, December 8, 2025, with otherwise identical wording. Videos uploaded before each channel type's date "will remain the same, as a long-form video on YouTube."
Both conditions have to be true. Square-or-vertical and three minutes or under. A 16:9 ninety-second video is not a Short.
The practical consequence runs in the direction people do not expect: you cannot opt out by uploading through the regular flow. Export a 1:1 two-minute cut for a client and push it to YouTube, and it gets categorised as a Short. YouTube's own answer to "Can I prevent my video from being turned into a Short?" is about geometry, not settings: "If you don't want your content to be classified as Shorts, use a wider aspect ratio such as 16:9 for long-form videos." The shape of your export is the switch.
The resolution ceiling almost nobody mentions
YouTube states a maximum, verbatim: "Note: You can upload Short videos with a maximum resolution of 1080p."
That single sentence rules out a lot of wasted effort. If you shoot vertical 4K on a phone and hand the full-resolution file to YouTube as a Short, you are pushing pixels past a stated ceiling. YouTube does not say what happens above 1080p — no promised rejection, error or downscale — so the honest reading is: there is no documented benefit to exceeding it, and no documented behaviour either.
Note what this is not. It is a maximum, and YouTube publishes no minimum resolution for Shorts. The figure "1080 × 1920" that appears on countless spec sheets is nowhere on YouTube's Shorts pages. The resolution 1920x1080 does appear in the help centre — in the recommended resolution ladder for the default 16:9 aspect ratio, which is landscape, and which is not the Shorts path. Borrowing that number and rotating it is how an unofficial spec becomes a quoted one.
There is no Shorts file size limit, and that is the real answer
The only file size ceiling YouTube publishes for uploads at all lives on its general uploads page: "The maximum file size you can upload is 256 GB or 12 hours, whichever is less." That connector is doing real work — it is not two alternatives, it is whichever bound you hit first. For a three-minute Short, neither is remotely in play.
So if you are hunting for a Shorts megabyte cap to compress against, there is no target to hit. What constrains you is upload time and the 1080p ceiling, not a published size limit. Check the official documentation if you need a current answer.
What to do when your file is the wrong shape or bigger than it needs to be
You have three real constraints to hit: square or vertical, three minutes or under, and 1080p or below. Re-encoding handles all three in one pass, and there is no reason to send unpublished footage to a server to do it.
Try it right here
Runs in your browser. Your file is not uploaded anywhere.
This runs inside your browser tab — the file is read from disk, re-encoded locally and handed straight back, so no copy of your footage leaves the device. For a QuickTime file straight off a Mac or iPhone, MOV to MP4 swaps the container with the same no-upload round trip, and all Clapr tools covers everything else. If you want to understand the trade rather than accept a preset, how to compress a video without losing quality walks through what bitrate and resolution actually cost you.
Gotchas worth knowing
Do not burn black bars into a vertical export. YouTube says this in two separate articles: "For the best experience, don't add black bars to the sides of your vertical video", and "For best results, avoid adding padding or black bars directly to your video." The reason it gives is that padding "interferes with YouTube's ability to change the player dynamically to your video size and the viewer's device."
Your Short will have padding on desktop, and that is normal. YouTube documents it: "For some video and device aspects ratios like 9:16 vertical videos on computer browsers, YouTube may add more padding for optimal viewing. The padding is white by default, and dark gray when Dark theme is turned on." Nothing is wrong with your file.
The encoding page is advice, not entry requirements. YouTube's recommended upload encoding settings page suggests "Container: MP4", "Video codec: H.264", "Audio codec: AAC-LC or Opus or Eclipsa Audio" and a "Sample rate: 48kHz". It also says outright that "No bitrate limit is required, though we offer recommended bit rates below for reference", and carries its own caveat at the top: "These features are only available to partners who use YouTube Studio Content Manager." Treat it as a good default, not a gate.
Fifteen files, then finish the details. The full sentence on batch uploads matters: "You can choose up to 15 short videos at a time, but be sure to click EDIT DRAFT to complete your video details before publishing." Queueing is not publishing.
FAQ
What are the correct YouTube Shorts dimensions? YouTube does not publish a required pixel size. It publishes a shape — "square or vertical" — and a ceiling of 1080p. The widely quoted 1080 × 1920 does not appear on any of YouTube's Shorts pages; 1920x1080 appears only in the 16:9 landscape resolution list, which is a different path entirely.
How long can a YouTube Short be? Up to 3 minutes. YouTube states this on three separate pages, including the upload flow ("Up to 3 minutes.") and the classification rules ("up to three minutes in length").
What is the maximum file size for a YouTube Short? YouTube publishes no file size limit specific to Shorts. The only upload size ceiling in its documentation is the general one — 256 GB or 12 hours, whichever is less — which a three-minute clip will never approach. Check the official documentation before trusting any specific MB figure.
Why did my regular video turn into a Short? Because it met both classification conditions: a square or vertical aspect ratio and a length of three minutes or under, uploaded on or after October 15, 2024 for standard channels. YouTube's stated fix is to use a wider aspect ratio such as 16:9 for anything you want treated as long-form.
Does uploading in 4K make my Short look better? YouTube states a maximum resolution of 1080p for Shorts and does not document any behaviour above it, so there is no published upside. Export at 1080p or below and spend the bitrate there instead.
For the same breakdown on the other short-form platforms, see Instagram Reels video specs and TikTok video size limits, or browse the rest of the platform limits guides.
All specifications quoted from the YouTube help centre pages linked above, checked 16 September 2026. YouTube has changed upload limits before and says so on its own pages — verify against the source before relying on them.
