YouTube Shorts vs Instagram Reels vs TikTok: Full Specs Cheat Sheet

YouTube Shorts, Instagram Reels and TikTok all converged on the same basic idea — full-screen, vertical, scrollable video — but they didn't converge on identical technical specs. If you're repurposing one piece of content across all three, here's what's actually the same and what still trips people up.

What's identical across all three

The good news first: the core frame shape is the same everywhere. All three platforms are built around a 9:16 vertical aspect ratio, with 1080×1920px as the resolution most creators export at. If you master one vertical file at that spec, it'll display correctly — full-bleed, no bars — on all three without any reformatting.

Where they genuinely differ

Length limits

This is the area that changes most often across all three apps, since each platform has repeatedly extended its short-form length cap since launch (all three started well under a minute and have since pushed toward, or past, several minutes for their "shorts" formats). Because these limits move, the safest approach is to check the current cap inside whichever app you're uploading to rather than relying on a number printed here — what's reliably true is that all three still favor content that front-loads the hook in the first couple of seconds, regardless of the technical maximum.

File size caps

Mobile-app uploads on all three platforms are generally handled through in-app compression, so the practical file-size ceiling you'll hit is less about a hard platform limit and more about upload time and your own device's processing power on longer or higher-resolution clips. If you're uploading a large master file, compressing it first (see our Video Compressor) makes the upload faster without you having to guess at a specific cap.

Safe zones and UI overlap

Every platform overlays its own interface on top of your video — captions, like/share buttons, the creator handle, sound attribution — and the exact position of that UI differs slightly platform to platform. TikTok and Reels both tend to place primary interaction icons down the right edge and captions/username toward the bottom; YouTube Shorts follows a similar pattern with its own icon set. If you're hardcoding subtitles or on-screen text into the video itself (rather than using each platform's native caption tool), keep that text centered and away from the outer 10–15% margin on every edge so it isn't covered on any of the three.

Cover images / thumbnails

Reels and Shorts both let you pick or upload a specific cover frame separate from the video's first frame; TikTok supports a similar cover-selection step. All three follow the same 9:16 proportions as the video itself for the cover.

A practical workflow for cross-posting

1. Shoot or export your master file vertically at 1080×1920 (9:16) from the start — this avoids any platform's auto-crop guessing where your subject is.
2. Keep on-screen text and faces inside the center safe zone, away from all four edges.
3. Trim to the length that suits the story, not a specific platform's technical maximum — shorter, tighter edits consistently outperform padded-out ones regardless of platform.
4. Export one master file, then re-upload the same file to all three rather than re-editing per platform — the shape compatibility means you rarely need platform-specific versions unless you're adding platform-native captions or stickers.
5. Compress before upload if the file is large, so you're not waiting on a slow upload for a file the platform will re-compress anyway.

What about landscape or square source footage?

If your source footage was shot horizontally — a screen recording, an interview, older camera footage — you'll want to crop it to 9:16 before uploading to any of these three rather than letting each platform apply its own automatic (and inconsistent) letterboxing or cropping. Our Reel & Shorts Size Resizer crops a video to the 9:16 frame (or 16:9 / 1:1, if you need those instead) entirely in your browser, so you get one consistent crop across every platform you post to.

Cheat sheet summary

• Aspect ratio (all three): 9:16 vertical
• Reference resolution (all three): 1080×1920px
• Length limits: vary and change frequently — check each app's current cap
• File size: practically limited by upload time, not a fixed number worth memorizing
• Safe zone: keep text/subjects inside the center ~80% of frame on all three

For the wider list — landscape formats, Stories, feed posts and more — see our full social media video specs cheat sheet.