· Updated · 6 min read · By the OptimaClip team
1:1 vs 4:5 vs 9:16: which aspect ratio for which platform
Use 9:16 for TikTok, Reels, YouTube Shorts, and any placement that plays full-screen by default; use 4:5 for the Instagram and Facebook in-feed experience and for LinkedIn; use 1:1 when a clip has to work identically across many placements or is built around a shared screen or slide.
The reason 9:16 isn't universal: on a scrolling feed (Instagram main feed, LinkedIn, Facebook), a true 9:16 video gets letterboxed or cropped in the preview, wasting the top and bottom. A 4:5 video fills the maximum allowed feed height without going full-screen, so more of the frame is actually visible while someone scrolls.
1:1 square is the safe default for repurposed screen-share content — a demo, a spreadsheet, a slide. Cropping that to 9:16 usually destroys the readable content; a square keeps the shared material legible with room for a caption strip.
There's also a production cost angle. If you shoot or record once and know you'll post to five places, framing your subject with padding on the sides lets you export 9:16, 4:5, and 1:1 from the same source without re-shooting. Frame for the widest crop you'll need.
Text placement changes per ratio. Captions and titles that sit comfortably in a 9:16 safe zone can collide with platform UI in a 4:5 export. Check each ratio's export, don't assume the 9:16 layout transfers.
Practical rule: make 9:16 your primary, export 4:5 for the feed-based platforms, and only add 1:1 when the clip contains screen-share or slide content that a vertical crop would ruin.
OptimaClip exports all three ratios from one project with the caption position adjusted per ratio, so you're choosing placements rather than re-editing.
Which aspect ratio to use on each platform
TikTok, YouTube Shorts, Instagram Reels, Facebook Reels, Threads: 9:16 vertical (1080×1920). Instagram and Facebook feed posts: 4:5 (1080×1350) takes the most room in the feed. LinkedIn feed: 1:1 or 4:5. X: 16:9, 1:1 or 9:16. YouTube long-form: 16:9.
See the full social video specs table for length limits alongside these ratios.
How to convert 16:9 footage to 9:16
Center-cropping a landscape video loses whatever isn't in the middle. Better options: track the speaker's face so the crop follows them, split the frame (facecam on top, gameplay or screen below), or use a blurred background behind a smaller landscape frame for content where everything matters.
OptimaClip's Smart Reframe tracks faces to keep speakers centered and exports each clip in 9:16, 1:1, 4:5 and 16:9 from one cut. More detail: how to convert horizontal video to vertical.
Safe zones
On 9:16 apps, the bottom of the screen holds the caption and username, and the right side holds the like, comment and share buttons. Keep captions and key visuals in the middle of the frame so the interface doesn't cover them.
Frequently asked questions
What aspect ratio is best for short-form video?
9:16 vertical for TikTok, Shorts and Reels; 4:5 or 1:1 for Instagram, Facebook and LinkedIn feeds.
Is 4:5 or 9:16 better for Instagram?
9:16 for Reels; 4:5 for feed posts, where it takes up more space than square.
What resolution is 9:16?
1080×1920 pixels is the standard for short-form vertical video.
Turn one long video into a week of clips
OptimaClip finds the best moments in your podcast, stream or webinar, captions and reframes them for vertical, and schedules them to 8 platforms. Free 3-day trial with 30 credits — no card needed.